Hi, bored7one4! Check out my system located in this
post. Be sure to read my system write-up after the component listing as it talks to why I chose the components for my requirements.
I build my system for $666. If I didn't have some of the items and didn't have rebates to cash in on, I think I'd be close to the $800 of the TonyMacX86 Budget Power Build 1 in the forum: Pre-Installation > Buying Advice section. (The first "sticky" from the bottom in this section talks to recommended builds: "Building a CustoMac: Three Complete PC Builds for OS X".)
Some of the components I used are no longer available at some sites, as are other's build. If that's the case, search with either Google Products search or on eBay, which has new, excess inventory. Unfortunately, there will be new Intel technology this Spring which is called "Sandy Bridge" and causing manufacturers to not replenish some items in the inventories. However, Apple may no adapt this technology until late 2011/12 time frame. So, go with stuff that works now as it is low risk.
Look at this
entry in TonyMacX86's blog for advice on graphics cards. Also check out the TonyMacX86 Wiki for more info in the hardware section.
Finally, look at the User Builds section (where my system description is posted) for ideas. You can always send a Private Message (PM) to someone about their system.
Good luck. Don't hesitate to ask questions. And, post what you're going to build before you plunk down your hard earned dollars so we can help head off any problems.