I have a new cpu I want to install. According to the motherboard documentation, it looks pretty straightforward. However, the instructions that came with the intel processor says it should only be installed by a profesional. Am I getting in over my head? Do I need any special tools or any thing? Looks to me like all you do is sort of push down on the clip that holds the heat sink down and unsnap a little latch and then remove the heat sink, unlatch the processor, pull up and its out of there. Install the new one, paying attention to the marked corner that it is installed correctly. Put the heatsink\fan back on, and I'm done. Can someone please advise. I don't want to screw up my computer.

Actually it is that straightforward, ALMOST!

Before u do anything, check with your mobo's manufacturer if your board supports the new CPU, and if maybe a BIOS-upgrade is necessary to make sure it does.
If you need to upgrade the BIOS, it should be done with the old CPU installed, otherwise you cannot boot.

When that's taken care of, just proceed as you said: remove cooler, lift arm, remove old CPU, plug in new CPU, close latch.
When installing and handling the new CPU, make sure to get yourself grounded (touch PC case) and do not touch the pins. (not a disaster if you do, but it's always better to avoid it)

Then, if the cooler has some leftover thermal paste on it, clean it with some alcohol or dissolvant, to get it all off.

You will need new thermal paste, 'artic silver' is the best (i think).
Apply a little of it on the CPU core (only a drop, don't drown the core), only a thin layer between the CPU and cooler is needed.

Reattach the cooler and you're good to go again. Try to get it on as straight as possible, without having to move it around too much, or levering it, as this could damage the CPU-core.
Also ascertain yourself the cooler is sufficient for your new CPU, some of the newer CPUs need a high quality cooler.
When in doubt, tell us which CPU and cooler you have.

Hope this helped you a little, since it's my first post here.

You helped a lot. Thanks. Actually, I have one more question. My motherboard documentation indicates that it can support either a celeron or pentium III 60/100 mhz fsb. It currently has a celeron 900 mhz. I have access to a pentium III, but it is a 133mhz fsb. Will this work or do I need to stick to the 100fsb. I have done quite of bit of reading on Intel's web site support. Its a little unclear but they seem to suggest the 133 fsb processer will work on a 100fsb motherboard.

Thanks again for your help.

Depends on the motherboard.
Some do, some don't.
Not only FSB and multiplyer settings matter, but you may be unable to set the CPU Core Voltage as required.
Checking with the motherboard manufacturer will again be necessary.

And even if it is possible to use the CPU, if the board will only run up to 100MHz, your CPU will run below spec. I think the multiplyer is locked on the PIII, so if you have a 933 (7*133) CPU, it will only run at 700MHz (7*100), if it runs at all that is. ( i just picked these numbers to make a point, don't really know if that particular CPU actually exists)

As said before, check with mobo's manufacturer.
If you can say which board you have, i'll check it out too.

Ideally you'd try to get your hands on a 100MHz FSB PIII.

I'll do some more checking when i get home, i'm at work now.