The cooler has to match the socket which in your case is an AM3+ (but check).
Check the spec of one you fancy which will tell you which socket it will fit. Amazon is a good place to start - search on "CPU coolers". Most current coolers will come with a variety of brackets that will fit all current sockets.
Most third party coolers are much larger than the stock cooler so you need to make sure it will fit in the case and also not foul the memory sticks or any expansion cards such as your graphics card.
Most require you to have access to the back of the motherboard so you will probably have to remove it.
Before fitting the new cooler clean off the old thermal paste. The new one will come with new paste.
HOWEVER. Before you consider a new fan its worth checking that the existing heat sink is not clogged with fluff as the system will run the fan at full speed in an attempt to keep the CPU cool.