I go up to Hamlin fairly often, stay on Indian Pete's Bayou on Barnhardt Road. I'll be there from 6/30 through 7/5, so hopefully the fishing will be solid! I haven't been there since the second week of May but from what I've read, the Pike fishing is hot right now. Mostly spinners according to the reports. They talked a lot about crawler fishing. One report said Walleye were hot as well, but another said they had turned off....depending on your prowess I guess!
My experience on Hamlin is that the Musky aren't quite that big yet, a few stragglers aside. The Musky stocked there a little ways back probably are still in the mid-20's range so some time yet to go to get some serious action. The Largemouth fishing has gotten progressively better over the past 10 years I've been going and I personally believe this lake is going to be a prime bass lake for years to come. Similar with Pike. Used to catch snakes every other cast with MAYBE a 22"-24" fish every now and then. Now we routinely catch low-20's with some occasional 30" and bigger fish.
If you're fishing Upper Hamlin, I'd suggest the large flat near the duck blind by the narrows, the large flat out in front of Barnhardt's and the area just East of the Wilson park boat launch. Lower Hamlin, my best luck has always been south of the entrance to the State Park. There's a pretty extensive line of bluffs that cut in and out all the way down the shore line with some decent weed lines that hold big fish the further south you go.
Also on upper, there are some nice bays on the south side of the lake east of wilson park where I personally had a big blow up two years ago on a buzz bait with a very prompt break off. 5 foot bay with nice thick cabbage. Normally by the 4th there'd be a lot of the lake choked up with weed growth but the way the weather's been, it may be perfect.
Anything with a white twister tail works well along with a variety of colored rattle traps and chatter baits.
4th of July fishing is always tough between the weather, weed growth, and lake activity but hopefully this year will be different. Best of luck!!
I'll be out in a Grey Bass Tracker with Orange decals. Feel free to say "hi" if we cross paths.