HELP!

Well I have spent most of the day working on our new blog. I found it to be pretty easy to get this far but now I am stuck. I can't seem to figure out how to make my headed picture smaller. I want to add all the cool stuff like a guest book, a ticker, music and Youtube videos but I don't know how. So I am going to beg my great blogger friends who are experts in this stuff for help. So in advance thank you Stephe, Donna and Wanda :) you all are the best.....