Hmm, well it will take a fair amount of javascript to accomplish, but it you are serious I can talk you through it.
First I would set up a seperate pricing.js file that has a buch of hashes that map products to prices, for example:
Code:
var procs = Object;
procs['amd30'] = 120.00;
procs['amd32'] = 130.00;
procs['amd35'] = 140.00;
procs['p22'] = 130.00;
From the form id you would reference the key to get the value from the hash. Multiply that by any modifiers that would effect the price (quantity, markup, etc) then set the value of the price field that computed value.
Let me know if you have any questions.