There are lots of options for traps and hand-liners. The crabs are there, but I went to Northside Park last weekend and it was just too shallow at most points. Most of my day was spent shaking off juveniles, and it was like that a lot last year too. They got some rain this week but I don't expect it to be much better. If you do go there, try to drop a trap in the Deep Water Lagoon pond. People might look at you like you're crazy, but I've caught several large ones there a couple different times.
You can try the piers behind the OC Convention Center on 40th, or Holt's Landing or Camp Barmes in Delaware (If I remember correctly you have to pay for access to both).
There's a nice Pier at "Public Landing" if you don't mind a drive to get there. I've never been there this early in the season so I don't know what it's like. There's also a pier at Isle of Wight that I've never been to, but it is just off the 90 bridge outside Ocean City.
If you want some privacy check the side streets on the left side of Route 20 heading out of Fenwick. They all back up to the bay and some have piers…but it’s hard to find the one or two spots where you would not be trespassing.