for a beginner, I suggest buying a small quantity of General Hydroponics 3 part flora series. just buy one pint of each. If you find you really enjoy it and want to expand, then you can find something else in larger quantities.

There are many makers of hydro nutrients and General Hydro is one of the best-known. They make good stuff.

I started with tomatoes and herbs. I bought my nutrients from Eco Grow, and I've had excellent results. it's the cheapest I've found. the nutrients are in powder form and added to water. I have a small 2-tube aero/nft hybrid 6ft long, the 5 lb box I bought has lasted me more than a year. as soon as I run out I'll probably buy a 25 lb box. they have different formulations depending on the type of plants you're growing, so check them out before buying.
I mix up the solution as a concentrate and keep it in a couple of 2 liter bottles. then I add to the reservoir until the PPM is correct. I was making weekly water changes, but I found that I can go 6 months just adjusting the PPM without any ill results.

Here is a link that might be useful: eco grow nutrients

Thanks for replying everyone, it is most appreciated! I've now bought some kit from a few different ebay stores and have bought some nutrients too. I bought the nutrients from the link below, thought they were reasonably priced, does anyone know if they are any good? As this is my first time I thought I would opt for price.

Thanks again everyone! Once I have some veg I will upload a picture to show how I'm getting on...fingers crossed!

Here is a link that might be useful: Glogrow

Never heard of them, but I noticed the prices indicate they're across the pond.
Anywho, if it's a complete nutrient (most are) then you should be fine. Maybe in the future something more refined will be called for, but as a beginner you're really just looking to make sure you enjoy it.

Hi Grizzman,

Many thanks for getting back to me and for your help, it is most appreciated! Apologies if this is a US site, I didn't realise! Happy gardening!