Having only started a couple of months ago myself, I can completely relate. Since my Brigand is now 50th, I dealt with the same problems. Here's the approximate path that I took.
1-20 Timorous Deep (Gorowyn Islands)
21-30 Butcher Block Mountains
31-33 Thundering Steppes
34-36 Enchanted Lands (accessed from Nektelos Forest dock)
37-40 Zek, Orcish Wastes (accessed from Thundering Steppes dock)
41-47 Steamfont Mountains (accessed from Greater Faydark, connected to Butcher)
48-50 Feerrott jungle (accessed from Thundering Steppes dock)
I liked Enchanted, Zek, & Steamfont because there are tons of quests that you can pick up and they're mostly given out in the same area. While Enchanted and Zek started to get really old, I've really enjoyed Steamfont Mountains. Also Butcher Block was fun once I understood how to quickly navigate the zone. (I never really liked Thundering since it seemed to be severely focused towards grouping and was ill suited for a solo player.)
Also should you start a new Evil aligned character, please try to start in Timorous Deep. Or really, any new character you build should travel there. (The city is relatively neutral, so any alignment of characters can do their quests.) Through the use of Magic Carpets, it's rather simple to make it over to the sarnak island chain. Being the latest expansion, the gear there us unbelievable. Some pieces of it I'm still using since they grant abilities that I couldn't find again to my 50's gear.
(Edit)
During most of this time, I played solo. So these should hopefully be applicable to you.
Edited, Apr 4th 2008 10:29am by ericsweeney