There are several forums online that specialize in this area. Webmasters discuss their experience with hosting companies and their servers in a lot of detail. You may also be able to get a coupon code or free setup with some of these companies. I'm not sure if I can mention URLs here. Use Google. Another way is to look for prominent websites and use whois to find the host they use. Then look for reviews. Sometimes webmasters who run sites will be glad to guide you if you use their affiliate link. Commissions are high on servers. These are also directories that compare dedicated server companies.
Generic advice: Don't just look at the things about your present host that you dislike and want to change. Also take a careful look at all the things you do like, and make sure a potential new host offers the same features.
There are several forums online that specialize in this area.
Watch how they react to client issues that come up and how quickly some solve it without insisting on opening a ticket. You can also get an idea as to who is reselling and who actually owns the server.
Stay far away from anyone who offers unlimited bandwidth and disk space. What they fail to disclose is this usually means unlimited slowness. Many of these hosts have no qualm with placing too many VM/VPS's on a single hardware host.