Check out any site very carefully. Do Whois searches and find out postal addresses, name changes, and the truth behind the claims and lies that are used on the internet. I looked at one school after another poster asked ans it had no postal address, which is enough for me to walk away- it's a site involving contracting and employing but has no address to receive legal letters.
There will be good places, but I get loads of links submitted every week from dodgy sites and do see the other side. Do you know how to do a whois search and a bit about how to find out facts that aren't on a webpage?
ESL is a profession that attracts a disproportionate number of suspect owners and managers at the best of times, so given the chance to do business at enormous distance and even more able to avoid employment laws.
A couple of years ago, there were a lot of one-man band teaching sites going up and after them came a wave of internet start-ups with big visions. A few have managed to translate those visions into profitable companies, but most pf the resty have either gone bust or rebranded or probably will soon enough, espcially as start-ups are basically comanies losing money or needing an injection of outside capital to have a chance to succeed. The current state of play in the economy means that many of these will struggle or go under. However, there are also those that will do well and attract students from bricks and mortar schools, so check them out very carefully first.