Kinda hard to make a rec without knowing what kinda chip you are interested in as it will make a diff on the MB you would need when it comes to overclocking. And I'd guess you would need to state if your looking for a matx or atx form factor.
For example the GIGABYTE GA-G41M-ES2H is a great board for overclocking dual core chips. Will push my e5200 to 4.16ghz 100% stable. With this board a chip that runs native on the fsb of 800 or 1066 you have overclocking headroom. The board will work with a chip with a native fsb of 1333 but does not have any overclocking headroom left.
If you plan on running a quad core chip and overclocking you need to pony up for a higher quality board such as the Gigabyte UD3R or P P45 or something similar
If your looking for a combo check my forsale thread in sig. Combo #2 could put alot of power in a small place with good cooling of course. Has been thoroughly tested @4.16ghz