Help with variable speed switch for inline fan

[BWC BayArea]

I have a quick question. I have a 2 speed 8" intake fan that blows a little harder than needed for its application as of now. I was advised to get a variable peed controller to control the flow. I realize this is similar to a dimmer switch (similar to what's used to dim a chandelier). My question is can I use a light dimmer switch? If so what info do I need to take with me to the store to ensure I make the right selection. I would appreciate a fast response from some1 knowledgeable, I wanna catch the hardware store b4 they close this evening. And no I don't want to take my fan to the store for better assistance, LOL. Thanks

 

[BWC BayArea]

Help with wiring, Needed ASAP

So by the time I woke up and got out the hydro stores were closed. Thanks for the info, but I'd rather go get it than wait for the mail. So I went to the local hardware store (right as they're closing) and grabbed a ceiling fan dimmer switch to hook up to my 8" inline fan (473/419 CFM) to control the fan speeds.

The way I tried to hook it up it ran normally in all positions (like there was no switch there).
2nd time when I slid the switch heard a pop and a spark flew, I unplugged.
3rd time it started up but was turning extremely slow when tha slider was in the middle. The top and lower position had no juice. Did I grab the wrong switch in haste or can I make this work??? NE1
Hope it didn't blow the switch. I wanted to have this hooked up by tonite. Anyone up care to help tonite?

 

[BWC BayArea]

Got a variable speed controller for my fan. Tested and it works. Made my day. +rep to blubullet for being the ONLY 1 that tried to help me. NE how problem resolve. This post can should probably be deleted. If u wanna c what I plan to do with it U re welcome to check out my journal in the signature.