WRT finding a decent AGP graphics card - Leadtek 7600 GT AGP. Paid £126 + delivery for the one I just bought to put in my Dads PC. See Legionaire68's post, they may be available cheaper soon.
I was really surprised how well it ran Oblivion (with HDR), Titan Quest, Company of Heroes demo, Far Cry (with HDR), Prey etc. This is with a cruddy P4 2.4 (@2.8) too. Ok so it won't let you play in very high res or with lots of AA, but if you stick to 1280*1024 max, AF-8X AA-Off, then it'll handle just about anything available today. IMO and I realize this is educated guesswork here, but it will allow you to play Crysis and have it look pretty good.