Look for recipes that use fewer eggs in proportion to the cream cheese (or Neufch�tel or ricotta or whatever "cheese" ingredient you're using) and very little or no flour. Eggs and flour are thickening and binding agents that will give a firmer texture. Also, try adding (or increasing the amount of) sour cream to the cheesecake mixture. I usually also add a tablespoon or two of fresh lemon juice. If the mixture is predominately cream cheese (and very little liquid), the cheesecake will be very firm when chilled.

Even more important than the specific recipe that you use, DO NOT OVERBAKE! The cheesecake will continue baking after you take it out of the oven, and it will become firmer when it's refrigerated. If you want a soft, creamy cheesecake, the center of the cheesecake should be jiggly when you take it out of the oven. Even the best recipe will be ruined if overbaked.

I've tried a lot of different cheesecake recipes over the years, and have gotten great results with nearly all of them. (Of course, I don't select recipes at random. Usually I try recipes that have been recommended to me or that come from serious cooks.) Unlike regular cake recipes which need to be followed precisely, cheesecake recipes are very forgiving. You have some leeway to adjust the quantities of the ingredients, as long as you don't make drastic changes.

One last tip -- I always use Neufchatel instead of cream cheese these days because it has 1/3 less fat than cream cheese. It often has fewer additives than cream cheese, which almost always have stabilizers added. I'm very fussy about ingredients, but I can't tell the difference in cheesecake. Don't use whipped cream cheese, though, because the quantities wouldn't be comparable.

Here is a link that might be useful: How long to bake cheesecake