The first question is, Do you want a real girlfriend or a an online girlfriend? I hope it’s the first. You don’t need an “e-relationship.” Also, are you looking for a serious relationship or to simply go on some dates. Clarify you motivation and that will determine which websites you go on.
Otherwise, it’s not hard to get started. Find a legitimate website, create you profile and upload some normal pictures of yourself—even some that aren’t the best. Make sure all the information is true and accurate and starting chatting with someone.
Find people NEAR YOU—that’s key. Unless you want to start traveling around the country (or the world for that matter).
Most importantly, treat people with respect and dignity even though you are online. People are people so don’t just stop communicating with someone if become uninterested in them—tell them, with grace and tact.