Okay Rex,
This will be my only warning. Stop where you are - step away from the keyboard - put down that credit card!!!! You are on very dangerous ground my friend! I was there about seven years ago thinking exactly the same thing.....just one nice size meteorite, something cheap - I can handle it. I was wrong - and I have maybe 40 kg of rock to prove it......so don't say you weren't warned!
There are several ways to move forward.....if you just want a meteorite, I'd recommend an unclassified NWA (Northwest Africa - usually acquired by the dealers in Morrocco). These are fairly inexpensive right now (as far as meteorites go). A nice NWA meteorite about the size you are thinking about will have a mass of about 200 grams. Prices can run from $.20 to maybe a bit more than $1.00 per gram depending on the condition, shape, and appeal of the specimen. I picked up a very nice kidney shaped NWA of 110gr mass with excellent fusion crust (a attractive surface layer resulting from the melting of the meteorite surface due the heat of the flight through the atmosphere) for $40 right here on Astromart. Check this site out for some good information http://meteorites.wustl.edu/id/fusioncrust.htm
If you decide to move forward even after my warning.....check out the ad in the Meteorite section of Astromart. There are several very knowledgable folks that offer items for sale from time to time. If you have any questions - I'd be happy to try to help. I'm not the most experienced guy around this hobby (a true understatement - for sure) - but I do enjoy buying and playing with these rocks, and I can help on some stuff or point you to the right people. Kidding aside - it is a great hooby, and blends well with astronomy. Gives you something to do on those cloudy nights.