Ancestry is one of my mainstays for genealogy research.
You don’t have to go to 3 or 4 different websites to search censuses and immigration records. They have a good and growing selection of previously-published family histories, biographies, military histories, and publications from various historical societies and organizations. These can be searched by name and/or keyword as well.
HOWEVER, this may help you delay your entry into paid research:
This is the LDS’ Family Search pilot project. I wish it had been available sooner. Keep in mind that this is a pilot project and more data are being added all the time. However, they have lots and lots of records there already. They don’t have all of the censuses (Ancestry does), but they have most of them. I haven’t seen immigration records on the LDS site (Ancestry has a fairly complete immigration records collection), but Family Search also has some collections from foreign countries that would cost you a lot more on Ancestry, assuming Ancestry has those collections.
While I agree that folks should not indiscriminately use other people’s trees due to many repeated errors and people just willy-nilly taking info from another tree and putting it into their own tree, there are some trees that are well researched (my own, for example) and took years to put together and verify. Anyhow, just perusing those family trees can give you an idea of places to look when/if you hit a brick wall. But never take one as gospel and without some verification on your part.
Ancestry allows members to include citations in their trees. Those of us who are serious will upload photos (when available) and images of documents or at least cite the name of the resource, when it was published, and may add an excerpt from the source. I have cited many vital records in my own, although I haven’t gotten around to digitizing and uploading them yet.
If you’re a member you can see the citations in trees and judge for yourself.
Another site that is of great benefit if your ancestors were here early and in New England is the NEHGS (newenglandancestors.org). Massachusetts was anal about gathering and digitizing records. If your ancestors were ever in New England, especially prior to 1900, NEHGS is invaluable. I believe they now have a reciprocal business relationship with ancestry and various newspaper archives.
However, the real gold in NEHGS is their early vital records and their many preserved early publications (deeds, court records, wills and probate, etc.).
As an aside, if you think we’re a litigious society now, we could not hold a candle to lawsuits in the 18th century. Suing someone for something was practically a national past-time. The good thing about that is that records were kept. 
Also, look up your local LDS family research center. They still have a few collections that aren’t available “out in the wild” yet. At one point I actually hired an LDS researcher who was selling hours on Ebay and was very pleased with their work. He had easy access to the record collections and sent the digitized records along with their findings. Saved me a trip or two.
Go to FamilySearch.org to see what holdings they have. Some of them are already on the pilot site noted above. If not, you can always find an LDS center, call them, ask them for the collection you’re interested in, and they can order it if they don’t have immediate access to it.
If you need any help or a new perspective, just let us know. It took me 3 years to track down my correct paternal line, and I’m still working on the maternal line. It’s a lot of work.