Not enough information to correctly answer your question. But here are two things that might help:
Your domain is currently using worldnic (or networksolutions) nameservers. If these were previously set to allow dreamhost to manage the DNS then you would want to change the nameservers back to ns1.dreamhost.com, ns2.dreamhost.com, ns3.dreamhost.com. Once the change take effect (hours) and dreamhost is again managing the DNS you should see the site again (assume that you didn't attempt/make changes in the dreamhost panel before changing the nameservers back to network solutions.
If on the other hand you always had network solutions managing the DNS, then you probably need to manually enter an A-record. First in the dreamhost panel, navigate to "manage domains" in the panel. Find the listing on that page for your domain, make sure it says "fully hosted" in the webhosting column, if it does then click the DNS link under the name. Scroll down, look in the non-editable records there will be a listing for an A record (probably the first line) write down the IP address that appears there. Then log into network solutions and create an A-record with a "value" that is the IP address we just wrote down. This change won't be immediately effective either, DNS takes time to propagate, usually 4 hours or less but could run over)
I'm sure I don't need to say this, but when updating things (DNS included) you should always know how it was before in case you need to revert. Document every change with an old value and new value etc.