I purchased a license from Plesk a few years back and had been with Layeredtech for four years or so. However, their price increases are crazy. When I started, my server was 79.00 a month. Its now 160.00. I was thinking softlayer. Can anyone tell me how hard it is to migrate all the Plesk domains, databases, backups, web files, mail, etc. fro, Layeredtech to another provider? This has been the only reason why I stayed. Almost tripling my costs were not in the plan. Is this hard to do? There is a lot of data. Like well over 20GBs of data.

Any suggestions?

Not very hard. You can use the plesk tools. I find using the plesk tools, with a combination of rsync, and iptables provides almost instant transfer and zero downtime.