Here are the things you need to consider when purchasing a motherboard:
1) Form Factor: Will the motherboard physically fit within your case? The simplest method for determining what form factor motherboard your case will accept is to count the number of expansion slots available at the rear of the case. While not 100% fool-proof, it's generally good enough. Seven slots means it will take an ATX form factor motherboard. Four expansion slots means it will take a Micro-ATX form factor board and zero to two slots generally means it will only take a Mini-ITX form factor motherboard. I would note that a good many cases with seven expansion slots will actually take both ATX and Micro-ATX form factor motherboards.
2) CPU Socket: Since you already know what CPU you'll be using, you'll need a motherboard that matches the CPU socket and wattage. In this case, it appears to be a 125 watt AMD AM3+ socket motherboard. You'll probably need to verify with the vendor that the board and CPU are compatible out of the box. In some cases, an older motherboard can be made compatible with newer CPUs by installing a BIOS update, but this sometimes requires a fully compatible CPU already installed.
3) Expansion slots: You will need to make sure that the motherboard you select has all the needed expansion slots you will want. If you're considering going with an SLI/Crossfire set up, then you will need to make sure the motherboard and at least two PCI-Ex16 slots that when both have graphic cards installed, will run at no less than X8/X8 speeds.
4) RAM Slots: If you haven't purchased RAM yet, then it's not that big of a deal. You can purchase RAM to match based on what motherboard you get.
-Wolf sends