There's not much you can do if your connections are being refused, but some people have better success by sharing more files (~100), opening port 6346 in a firewall , and setting up the router (if one is used) to help others connect. You can find most of these suggestions in the Tip of The Day and the User Manual in the LW Help Menu. I read somewhere that running a couple of hours each day also gets you recognized as a reliable host.

I just checked my stats--I was able to accept 1,200 connections this weekend, but 25,000 were rejected, mostly because all the slots were filled. As the network gets more people willing to run as ultrapeers (accepting incoming connections) and people willing to share, connections will be easier for everyone.