I'm going to get two hosting accounts with two different providers and I'm wondering if there is a simple way to make it so if my main site goes down, users will automatically be taken to the other one. I want my main site to be normal but my secondary site to simply hold a maintenance page so users know there is a problem.
If you sign up with DNSMadeEasy, you can host your DNS with them and at the same time sign up for the DNS Failover service which will do as you need. Basically, your DNS Servers cannot be hosted on the server which may go down.
I've purchased DNS Made Easy with Failover... can I implement it with my current site without causing any problems for my users? I don't want them to notice a thing. Also does the TTL have to be set low for Failover to work well or doesn't it matter?
Yes, you can. At DNS Made Easy, set up the DNS as you require it. Wait 24 hours. Then just change the DNS Records at Godaddy to point to the DNS Made Easy DNS. Do not delete any records from your current DNS Servers. So that during the time of DNS propagation, some may use your old DNS Servers and some would use the new one. As long as both are up, you should not experience any downtime and no one will notice any difference. Yes, the TTL should be set as low as possible. Check the notes in DNS Made Easy about this. Have fun.