I use Newegg for all kinds of PC "stuff". Fans, RAM, Video cards, you name it. Great prices.
One thing that's absolutely critical, when working with internal PC parts, like RAM: Static protection!!!!
You MUST ensure that you don't static the parts. That's why they're in the odd blue packaging. It's static proof. But when you take it out, that protection's lost. One step across a carpet, and you may have a small paper-weight if you take the part out before you touch the PC's metal frame. ALWAYS, at the least, touch the PC's METAL frame with some part of your skin before removing the static proof bag. Best is to have an Anti-stat wrist band, connected to the PC's metal frame. They're cheap, and readily available.
I was a radar tech both in and out of the military, and I've seen SO many parts destroyed by static. Remember, the little bitty spark that jumps to a door-knob, for example. If you can feel it, even if you don't SEE it, is 50,000 Volts. No current, but the voltage is what destroys PC parts, from chips on up.
Be cautious!
Have fun all!
Pat☺