NBC's "Who Do You Think You Are?" pre-dated my interest in genealogy, but I didn't start watching until after I'd gotten into things. Its a mildly interesting look at celebrities' genealogical lives / a commercial for the website ancestry.com.
I watched the recorded episode of Reba McEntire's episode last night and the "go use ancestry.com" plugs are coming fast and furious as celebrities bust out "their" Apple Macbooks and do a first-name-last-name search and then explore what highly-paid professional historians and genealogists find for them.
If you've explored ancestry.com and taken a spin with their 14-day free trial (as I have) you've done that and exhausted much of what you might find useful. But as I'm not inclined to pay professional historians and genealogists to find my 4GRGR, and I cannot tool around the country poking into local archives, I rely HEAVILY on online resources of the non-paid variety.
If you are at all like me in this way (cheap and tethered to my desk/hometown, and with roots in Northern New York) you'd find this resource invaluable:
Its a searchable archive of newspapers from these Northern New York counties, dating back to the 19th century. The PDF scans of newspapers are OCR'd to be searchable text. While not perfect, they are an excellent source of information about known relatives from that area and that time. Searching can be by entire county or by selected newspapers within a county. Access the page above at this link. I've found tons of stuff on my dad, who was something of a local, high-school sports phenom in his day.