Cleaning the chimney
 

How often should this be done and can I get a kit and do it myself or is it better to have a professional do it?
I usually burn those fire logs, not regular wood.

There are kits you can get that are pretty inexpensive. Since you don't burn "real" wood, you'd think your chimney would be cleaner, but that's not necessarily the case. It's kinda like your stove: needs to get hot and stay hot to burn off the creosote and other materials that the burning fuel leave behind. And firelogs generally don't get that hot. If it's been more than 2 or 3 years since you've cleaned your chimney, get a pro to do it. Once it's cleaned, get a good chimney cleaning kit and clean it in the spring and again in the fall. Note: chimney cleaning is really dirty work, so be prepared to look sooty (remember chimney sweeps?)

Fireplace cleaning
 

This website will help to guide you:

http://doityourself.com/fireplace/index.shtml

Also visit my business website for do it yourselfers like you:

http://lehighrug.com/id177.html

Hope I was of help. :)