Can't help you with the griddle but I use an All Clad Stainless pot for soups, pasta, etc. Works great.

My 12-qt stockpot is Tramontina from Wal-Mart. It's lightweight, which is nice when it's full, and it works very well on induction. I am pretty sure they carry larger sizes too. From everything I read, it seemed that clad sides (as opposed to just the bottom) are not necessary especially for boiling/simmering when using induction, which means you can choose whichever stockpot appeals to you most based on looks, handle feel and price -- provided a magnet sticks, of course. My everyday pots are Farberware Classic (the new version works on induction) because I prefer the short-ish handles for a variety of reasons.

I don't have a griddle, but all my pans are cast iron and they work great for pancakes etc. The iron griddles I looked at have a raised rim around the top and bottom, and I don't know if that is enough to prevent the induction field from working. Maybe someone who has used one will weigh in. If that doesn't matter, or if you can find one with a flat bottom, then I would highly recommend a cast iron griddle.

I would go with DeBuyer Mineral Steel pans and probably a Chef King carbon steel griddle.
16 qt pot is probably best to go with a All-Clad stainless or similar.

Induction does not require physical contact between the cooktop and the pot or pan for the energy transfer. (In fact the Ceran "glass" top of the cooktop itself is a physical barrier between the energy source and the pot or pan.) As long as the relevant parts of the pot is close to the cooktop, a small ridge around the edges (or even feet) on the pot will not reduce the effectiveness.

In any 16-quart pot, whatever the energy source, the cooktop will heat only a small part of the pot because the pot will be quite tall. Within the pot, the heat circulates by convection of the liquid contents from the bottom up. A clad construction in such a pot is basically a complete waste; you would be better off getting a pot with insulated sides (you will not find one, but stainless steel is not very conductive) to minimize heat loss to the kitchen through the pot's sidewalls than getting a pot with conductive sidewalls like an All-Clad. To eliminate hot spots on the floor of the pot, a conductive disk bottom construction is helpful, however.

I'm with Northcarolina--I have a Tramontina stockpot that came with a huge set of Tramontina tri ply from Walmart and it works just great. I didn't spend much on the whole set at all, which makes me feel justified in rounding out my cooking arsenal with pieces like the Staub Grillpan, round coquette and soon to come, a Demeyere or Mauviel saute pan. :-)

Best of luck. You're gonna love cooking with induction.

Has anyone used the jcp Home cookware for induction. They have a large all purpose pot with the teamer/pasta pot that goes inside. I think its 8qt. I miss my steamer basket for veggies that I had with my non induction cookware and of course the steamer basket doesn't fit in my induction pots.

Had to replace my 16 year old Calphalon when we replaced our electric coil cooktop with a Bosch induction. Chowhound users spoke very highly of Tramontina so I bit. I love the stuff. Cooks like a dream and like my Le Creuset, soak it a bit and clean up is a breeze.

I got the cheaper set, adding on the 1 quart and 8 quart pots with the steamer insert and also the 12" fry pan. Along with my La Creuset pieces, I am quite happy.

Volrath makes a great stock pot that is tri-ply all the way up, not just a clad disk. The price is comparable to the tramontina, which has only the clad disk bottom. Depends on how much the price difference matters to you (I think it is about $10 difference).
I have a lodge cast iron "griddle" that is round. I used it to make pizza when I was eating carbs. Now I use it to grill burgers/steaks, etc..
I use it on my largest burner. Since it is almost 19" in diameter, I wait till the pan is hot--and it will be hotter where the burner actually covers the pan. Mine is a Lodge and I do not know if they make anything smaller.

I bought an All Clad square griddle - it works great!
I have an eclectic collection overall
All Clad
Staub
CIA
Calphalon
DeMeyer
Etc

I am watching the giant stock pot as my largest is 8qt and thinking of 12 or larger

Buzzing is most noticeable on layered pots but the heat distribution is better than on iron alone. Also, the buzzing is worse until the pan warms up the layers.

wallycat: "Volrath makes a great stock pot that is tri-ply all the way up, not just a clad disk."

Then that would be a great pot to purchase if the goal is to use the stockpot as an auxiliary heat source for a too-cool kitchen. It would be a poor choice if you hope to use the energy imparted to the pot from the cooktop to heat the contents of the pot, because the conductive sides will leak the heat from the inside of the pot to the kitchen outside.

I love my 16 quart Le Creuset stock pot. It works great on my induction cooktop.

Wallycat, my tri ply Tramontina cookware does not have a disk on the bottom. Maybe some of them do, but the ones I got from Walmart do not. I do not like disk-bottom cookware on my induction cooktop. I have some and stopped using it because it tends to be noisy.
Cj

cj47: "I do not like disk-bottom cookware on my induction cooktop. I have some and stopped using it because it tends to be noisy."

I think you are making the error of coming to general conclusion based upon a small sample of experience. We have been using induction cooktops for a dozen years, and have encountered only one pot that sometimes whistles. (Whether it whistles or not is related to the level of liquid inside the pot.) Although the whistler happens to be a disk-bottom Demeyere Apollo, we have other Demeyere Apollo disk-botom pots that never whistle, and we have several other disk-bottom pots made by other manufacturers, such as a pair of Kuhn-Rikon pressure cookers, that never whistle. The issue is not with the architecture of the pot, but with the pot's specific resonant frequency that excites its bell mode; and all metal pots, whether or not they have disk bottoms, can have bell modes.

Beyond the bell mode, if the sandwich of metals in the base disk are not well bonded, they can rattle against one another if so induced by the frequency of the induction field, or by a sub frequency such as 120 Hz from the rectified power sent to the induction control.

Also, I suspect that bonding can be good enough when a pan is new, but if overheated (easy to do when one is new to induction) the disk layers in some constructons may be de-bonded.

kas

I had a lovely surprise after our induction cook-top was installed. I've had the All-Clad tri-ply for years, but also have one ancient 25+ y/o Farberware stainless steel pot that I love. It works on our new induction cook-top! No buzzing, no humming. It is a heavy steel (heavier than the old Revere copper bottom pots) so maybe this is why it worked. I wish I had a whole set of this stuff, mostly because the interior is much easier to clean.

Regarding a griddle, the pan I use the most on my induction cooktop is a steel comal I bought at a Mexican market. It was probably less than $10 and I use it almost every day. Grilled cheese, pancakes, I can even pop it into the oven to cook pizza.

Mine looks like this:

http://www.dvo.com/OldFiles/comal-tortilla-pan.html

I have a set of "Emeril" ware, made by All-clad but way cheaper. Got it ad BB &B for less than $300 with 20% off coupon. I really really like it.

I also have an enameled coated cast iron dutch oven I got at Sams club for $40 - and I don't see any difference between it and the LeCreuset brand.

For a griddle I think I'd just get a Lodge cast iron one.

I also had 2 nice surprises after getting my induction. A stock pot (stainless) and a pot that looked like a pressure cooker but had no lid, both my deceased mother's, worked on the induction. I was really sad at the thoughts of giving up those 2 pans (the pressure cooker one was my fudge making and popcorn popping pan because it had such a thick bottom and nothing burned) so I was thrilled, tho surprisd, that they both worked! I think our mothers really knew how to pick out cookware or they just made things better 40 years ago (well of course they did!)