Hello Beardzilla,
I have never made my own nutrients, although plan to sometime in the future. But I have found a recipe from the university of Arizona for hydroponic tomatoes. It's also a great site for all kinds of information on hydroponic tomatoes.
Tomato Nutrition

Again I have not made my own nutrients but I have found a few places that sell the mineral elements.

Cropking ( they have an online catalog, and you can also call them directly)
Hydro-Gardens ( their website is a bit confusing to me, but they do sell the mineral elements, so I would just call them)
Eco Enterprises (I didn't really see the individual mineral elements listed on their website, but I know they sell them. I have the new catalog and their listed on page 11 in the print catalog)
Verti-Gro (I'm not sure if they sell the individual mineral elements, but you can call them and ask. They make their own brand of fertilizers, and their much cheaper than most)
Spectrum Chemical Mfg. Corp. (this is a new one that I have found, and I haven't had time to really see what they have yet. But they do sell to the farming and hydroponic industry's, and I have the 2011 cataloge)

Sorry I had the wrong Spectrum company, here is the one that I have the catalog for. Not sure if they sell the mineral elements, but if you call them they can at least tell you where to get them if they don't have them.

Spectrum Technologies, Inc

Depending on where you live, but for me a local agriculture supplier sells calcium nitrate, magnessium sulphate and monopotassium phosphate by the kg, far cheaper buying it this way than a chemical supplier as you know. You also might like to check out daniels nutrient calculator http://scienceinhydroponics.com/

beardzilla;
at the bottom of the main hydroponics page is a function to search this forum. both of these issues have been discussed extensively here within the last year. try inputing 'nutrient forumla' and read to your hearts content. a word of caution, some of the threads have some pretty heated flame wars, so just try to skirt those parts.

I like Tomato-tone. I mix one tablespoon per gallon of water and aerate it for a day. A 4-pound bag costs about $6 but will make ~400 gallons of nutrients!

Mike

You can mix your own from the individual elements, but may get expensive buying all the individual components since many of them come in 25lb bags. You can purchase commercial grade (dry) nutrients already premixed for pretty cheap some places.
CPS or Crop Production Services is nationwide and sells both the pre-mixed formulas and individual components, you may want to see if there is a location near you.

The company Hydro-gardens that HomeHydro put in his post does have a confusing website, but they do sell the mineral elements and in as small as 5lb quantities so you may want to check them out as suggested. I have not visited the other sites, but am going to check them out.
(Thanks for posting HH, would be cool if there was a page in this forum just for links!)

Furthermore I would follow grizzman's advice and search the forum for additional info, there is a ton of discussions out there.

While the idea of mixing pure chemicals seems attractive it would be a very cost ineffetive way to proceed. The cost of purifying each of the chemicals would be far greater than simply re-formulating and re-mixing one or more of the commercially available fertilizers used in land based farming. There is a massive industrial base already established for chemical supply and while a commercial "Farm" procduct will not be sufficient, it will supply the primary chemical requirement. What will then be needed is to figure out what else is required in terms of chemical requirement and what, if anything, is needed to get the "Farm" fertilizer supply into a form that will dossolve in water (i.e grinding, heated solvation etc).

This thread is nearly 2 years old.