There is a pretty decent summary of drift alignment here on the Ice in Space forum:
http://www.iceinspace.com.au/63-405-0-0-1-0.html
I'm rather old-school and use an illuminated cross-hair eyepiece to do my drift alignment. I find it takes roughly 30 minutes to get an alignment good enough for long-exposure photography. As can be seen from the above posts there are many ways to achieve a good polar alignment so find one that works for you
