OSC help

I need help with a website. There's a few things I'd like to modify on the website, and a couple things I can't get to work 1. For some reason I can get the prices of the attributes to add to the total. SO I need some help with this. 2. Is it possible to make products attributes? Like say I'm selling hard drives. and I'm also selling a computer. When they're customizing the computer and they go to harddrives, it can display one of the harddrive products we carry 3. Paypal has issues with the checkout. When people pay with paypal, they seem to not click the link that goes to the final step in OSC. Which means we get the money but not the order. --------- so - I would love if someone could just help me out possibly for free by leading me in the right direction to the right contributions or whatever since it's not really work. My main concern is 1. and 2. If not, I can't pay much for it