General resources
This blog post on Fluent in 3 Months is a great starting point for those who have no idea where to begin. But I also gathered some individual resources that you may want to check out in addition to those mentioned there. See below for those resources:
Videos
Below is the first video of a series of Scottish Gaelic lessons. The videos move at a rather slow pace, but some may find this pace helpful.
For those that prefer bite-sized lessons, you may prefer these lessons:
Websites
These beginner lessons do a great job at explaining the basics: http://www.learngaelic.net/beginners/beagairbheag/index.jsp
Memrise has plenty of courses for learning the language: http://www.memrise.com/courses/english/?q=Scottish+Gaelic
Polyglot in Progress 