The lighthouse is open year-round but the days and hours do vary, depending on the season that you will be visiting. You can find out all of that information on their web site which is updated often. While visiting the web site, you can also read about some of the lighthouse's history, facts and get driving directions to their location.
You can walk around the lighthouse grounds which are beautifully landscaped for FREE. You can check out all of the flower gardens, the butterfly gardens and around back there are some benches that you can sit on that are located on the sea wall which gives you a beautiful view of the Atlantic Ocean and Hereford Inlet. Matter of fact, I think this location is the prettiest on the entire Wildwood island.
You can visit the gift shop to pick up some souvenirs which include your typical souvenirs, lighthouse history books, maps and other do-dads that you typically see in a tourist-attraction style of gift shop. I would say that their prices on souvenirs are a little high (in my opinion).
The next time you head down to Wildwood, Avalon, Stone Harbor or Cape May in New Jersey, make sure you stop in and visit the beautiful Hereford Inlet Lighthouse! You will be glad that you did!