First please read through the Newbie FAQ:
http://www.shrapnelcommunity.com/thr...5&o=31&fpart=1
Section 17 has a bunch of strategies.
Basically, in the beginning, concentrate on expansion and research of whatever supports your strategy. Expand, expand, expand. Try to get another colony tech as soon as you can. When you meet other empires, try to initiate at least a Trade Alliance while you fortify your borders. Mines are a great initial defense agains the AI. Eventually build fleets to "conduct military operations" in enemy systems to expand/conquer the AI empires. Read the section of the FAQ on the "Mega Evil Empire" because eventually agains the AI, you will become the MEE and the game seemingly will go from great to terrible in a couple of turns. Keep at it!
Slick.