Squamish is covered in a grid of amazing singletrack mountain bike and hiking trails that would take a lifetime to discover and explore on your own. Just like no one would ever come to climb in Squamish without a guidebook, runners and bikers should not go anywhere without this map.
The map is available in paper at most of the local bike and outdoor shops for around $11 and online as an iPhone App for $10. (Search for: Trailmapps Squamish)
The paper version is nicely sized with a large area view of everything between Black Tusk and Murrin Park while the reverse has the meat with all the Squamsh trails marked.
The App is easily worth the buy. With GPS running, it will show you exactly what trail you are currently on and makes it much easier to navigate some of the more confusing sections. Luckily, a large area surrounding Squamish has cell service (but not everywhere) so it is handy to use mid-run.
Whistler and Pemberton maps are also available and are just as cool.