A while ago I purchased a domain name and had my friend host it. Since it wasn't really my server I just had it URL redirect to some folder in her site. Later she changed her host, and I left. Now that I purchased my own server i'm trying to put that name as my domain but the DNS won't resolve. help please.

can you provide any more details? ie, what did you change in the dns record, what's your domain, etc.

my domain is http://elysiumdream.net

when I had to URL redirect I used dotsters DNS like NS1.dotster.com or something like that, then when I switched to rack shack I changed those names to the ns1.rachshack.net and it won't resolve to the right server. it keeps on trying to get to my old host

as far as I can see, your nameservers are listed as:
elysiumdream.net. name server NS2.RACKSHACK.net.
elysiumdream.net. name server NS1.RACKSHACK.net.

but, when I attempt to get an A record for your domain, I get this error:
Host elysiumdream.net. not found: 2(SERVFAIL)

This, as far as I know, means that ns1 and ns2.rackshack.net have no record of your domain. Make sure these are the correct name servers, if you're not sure ask rackshack.

Have you contacted RackShack support about this yet?