You should look into Gigabyte's DS3 boards. They usually have the best price-to-performance ratio.
I'd recommend the Gigabyte GA-P35-DS3R, which uses the new P35 chipset. This one is Gigabyte's replacement for the well-renowned GA-965P-DS3, and it might even become more popular than its predecessor.
If you really need Crossfire support, then you should look at Asus's P5K series (which also uses the new chipset).
For example, the Asus P5K (which is the "vanilla" board in the P5K series) has two PCI-E slots, supports Crossfire technology, and it also has eSATA, which meets all the expectations you've stated.