Good words from Tacroy!
When you say you "have access" to these three apps does this mean that they are all free for you to install now?
If so, well, congrats on having a lot of good software!
It's going to take some time to extablish what will become very significant over time, and that is a workflow that will go from bringing photos into your library, properly organizing them in a way that is efficient for doing various tasks, and if you shoot in the Raw format how to handle your development between Raw processing that you would do in Lightroom or the Photoshop Camera Raw plug-in which is in CS5 and in a limited sense in Elements, and pixel-level editing which you will only do in CS5 and/or Elements.
Part of that process will be to choose between Lightroom and CS5/Elements as a "workflow center" app -- this would be where you begin working with and organizing your imagess and can be a major decision. Many people go with Lightroom, many prefer Photoshop, it's personal preference. Those of us who go with Lightroom, even though we also have Photoshop, do so because by design it is about a Photographic workflow and its interface is constructed around that, integrated to make our most common tasks quickly available.
Photoshop, on the other hand loads so many tools in there and can do many things that Lightroom is not designed to do -- it packs a lot of power and in fact also has the Raw processor engine that Lightroom has so if you have CS5 you don't "need" Lightroom. It's then whether Lightroom lets you work more efficiently or not.
Elements is, by the way, "Photoshop Lite" -- it has many of the tools that CS5 has but in a more trimmed-down package. There are in fact people who do a lot of work in Elements for that very reason even if they also have CSx.
Here's what I'd suggest:
Start with Lightroom and CS5 and really get to know them. Get a book, 2 books, three books on each and take your time reading, working alongside as you read, and going for online tutorials. Take your time -- Lightroom is something you can take in a lot in a reasonably concise period of time, but it's important to apply yourself (start by reading the very informative Help).
Photoshop is a much larger app with a huge learning curve that just has to be slogged through a step at a time. Get proficient with Lightroom and slog through learning Photoshop and, in time, check out Elements and see whether you may want to do things there instead of the "big footprint" of CS5!
There are three good Lightroom books by Scott Kelby, Vicatoria Bampton and Martin Evening -- an Amazon.com search will turn them up.
Photoshop has an immense library of books which will cover bases, but few will attempt to cover all. Two "standard" books which take a broad approach are by Martin Evening and Scott Kelby -- titles are very similar, google or do an Amazon search for "Adobe Photoshop CS5" and either author and you should get good hits.
Two other books that you might look at are this Scott Kelby book:
http://www.bhphotovideo.com …cott_Kelby_s_7_Point.html
And this book "Layers" by Matt Kloskowski
http://www.amazon.com …ful-Feature/dp/0321534166
And then, the online resources: the site Lynda.com and KelbyTraining.com are for-pay services that overflow with good stuff, and there are also tons of stuff you can freely check out such as AdobeTV and LightroomKillerTips.