my fan on my computer has just started to run really loud. i have had this happen a few years back and had someone replace the fan. i was thinking of trying to do it myself this time. what info do i need to know to replace it? where is the best place to go? what is one fan i should get over another? thanks.

You need to know which fan needs replacing (CPU, motherboard, video card, power supply, case, etc), the size of the fan (60, 80, 92, 120mm, etc), & the plug type (3-pin, 4-pin, molex, etc). They're rated at different rpms, different airflow, different bearing types, different noise levels. Didn't think so much was involved, right? http://www.newegg.com/Case-Fans/Sub...
If it's the CPU fan, you may want to change the heatsink/fan as a unit.
Is it running loud because of increased fan speed? If so it may simply be doing what it's supposed to do. A computer case is like a vacuum cleaner. The accumulated dust and dirt can restrict heat dissipation which in turn requires more air flow, or increased fan speed. Before you buy any fans, spend $2.39 on a can of compressed air, remove the side panel and blast away. One kudo. Hold the processor fan blade to prevent it from turning when dusting the heat sink. Also, unplug the psu, ground yourself on the case, close your eyes, hold your breath (the last two were humour). This needs to be done periodically so you're not wasting two bucks even if it is not the resolution.
