Most certainly visit that link above. There is a lot of information there that will make conversation much easier for you on the threads.
For a 55 gallon tank and your first saltwater tank, I would suggest a fish only with live rock. This will be far less expensive and will ensure that you enjoy the marine side of the hobby before moving towards a reef or tank with invertebrates.
The important decision to make up front is this: sump or no sump?
You will find information on sumps included in the above link.
After you decide this, then we can make equipment suggestions and help with the live rock question. In fact, we can give you exact suggestions and links to internet sites which will save you some money on equipment and rock.