Suggestion?
Open a good base picture you have taken and start moving the sliders... make your own pre-sets by learning what they do, and what changes are made.
I suggest paying close attention to the Clarity, Saturation & Vibrancy area when messing around, that's where much of the magic happens. Also, contrast.
I have to give a +1 here to Sabbath's comment! The truth is that whether we're talking seasoned pro or complete novice, no two photographers are alike and quite often situations can vary from one to another. Aside from the idea that "presets" may or may not provide the results you are looking for and may or may not be applicable to all situations (in other words, it's likely to be A LOT of hit or miss, trial and error to see IF a given preset does what you need for your own work), I think it's probably a good idea to learn and get used to how all that stuff works in any case, so
you can get the most of
your images. After all, the whole point of processing your own images (as apposed to taking them into Walmart and letting the machine do it) is so that
you have the control.
If we were talking about specific "styles", say creating images with a vintage cinematography look, such downloadable presets could have an advantage for someone just learning, however to me at least, it sounds like the OP is just trying to learn how to adjust his own images for a better over-all look...and I think most people usually benefit more from simply learning how to do it themselves.
The other thing I would add is that if you're not sure how you want (or think) your images should look, snoop around online and find work that's comparable (in terms of genre...if you shoot landscapes for example, look for comparable landscape images, as baseball and football images probably won't help) and use those as a base reference for doing your own adjustments. This alone will get you used to working with the controls (sliders) and give you a sense of how you want your images to look. To use an analogy here, as a musician when I'm working in the studio, I will often reference the work of other artists I admire when mixing and doing eq work and such...for example, Steely Dan's "Aja" is considered by many as the ipso-facto standard for
good recording, so I will listen to such material to get my ears "warmed up" so to speak. I think the same is true of photography (or other art forms in general)...it's always a good idea to reference the work of others you admire, to give you some sense of where you want to go with your own work.
Just my own opinions, but again I have to agree with Sabbath there...learning to do it yourself instead of relying on downloaded presets will likely give you better images once you understand the nuances of the controls.