I'd agree with the above comments. As noted, its been asked here quite a bit.
1) Don't rush into buying. Try as many as you can and learn proper stance (it's likely something different than what you are doing now, and shotgun fit. The two are closely related).
2) Ask people to try their shotguns. Club members may not offer, but I bet 99% of them will let you shoot their guns if asked knowing that the options out there are plenty and prices vary widely. Fit means everything. Try to be neutral with opinions. Everybody has one, and often people will say what they have is the best.
3) Consider taking shotgun courses on proper fit and shooting first. You can often rent guns and with choices, they can select a gun that better fits. Using guns that don't fit will cost you 1000's in ammunition and frustration.
4) Once you know what fits, look for a proper gun. Buy quality. If in doubt, stick with the BBB's (Beretta, Browning, Benelli). There are others, but you're safe with those.
5) Remember that advice is often given, but not always correct. That said, some of it is and it's valuable when free. There are A LOT of back seat drivers with shotgun shooting. The general rule is to not give advice unless asked for, but that's rarely followed. Keep in mind some good shooters can't teach, and some who know well can't shoot. In other words, take it all in stride and do your own research. Read some books, discuss with qualified shooters, etc.
6) Also note, not everybody measures or sees the same. Distances quoted are often received or given differently. Some will say shoot at the front of the clay, when it should be 3' ahead. This will frustrate you. You'll get to a point eventually when you don't measure and just shoot. It may be best to start this way by not focusing on people yelling what the lead should be.
7) don't apply the same lead to every shot. Even the same clay on different days can change depending on wind. The beauty of EVERY shot in clays (non/typical sports) is every one is different. They all need to be read, and shot knowing they are different. Don't focus on where to aim, but what the clay is doing. Aiming is often assuming the bird is keeping the same flight path, which it's not.
8) Don't track clays forever. The farther you let it go, the harder it'll be to shoot. Shoot quickly, even if it has to be instinctively. You'll expand on this once skills improve. Vice versa, if they clay is getting closer, it's not always getting easier. It's change of direction during flight is increasing, and your shot pattern is decreasing in size.
9) Don't be afraid to shoot repeated clays. You need to work on the basics before getting better. Learn the more typical shots and how they differ with position change, then start adding variation once you are feeling more confident. Don't jump head first and struggle for years. ($$$)
10) Lastly, some fellow shooters will help you learn. Some won't. Know who to shoot with.