Hi Sherri! Welcome to AA. I've found this video
to be a great help in resealing leaky tanks (or in my case, the silicone was so blue from meds, it was ugly!) Also this link has good written instuctions DIY Tank Re-Seal Full Instructions
I'm assuming you already know all about cycling properly (with an ammonia source), but if you don't click the link on starting an aquarium (below) to get a good overview.
As for fish, what are you looking for? Bright colors? Schooling fish (so relaxing!) A couple big centerpiece fish? A fun community? Active fish? Let us know more so we can throw out suggestions!