If u aint gona overclock, stock heatsink is all u need. If u bought OEM version of the CPU (no heatsink) then thats just a case of stupidity as stock heatsinks don't normally add more than $ 15 to the overall price.
If ur case has a side window then i can understand the use of third party coolers.
The ASUS A8V will fit even the largest breed of heatsinks. I recommend the use of ZALMAN CPNS 7000/7700 LED. Its not only quite, its also one of the best.
There are tons of coolers available, all of them will do thier job. Its just a matter of personal likings, some like thermaltake others don't, its up to u whatever u want to buy.