It really depends on what the person likes from a genre standpoint... you'll need to recommend based on what they like the best: sci-fi, horror, thriller, military, sports, or the mob.

I know that many may disagree with my generalization, but here's how I would break them down into the categories:

• Infected (Sci-Fi/Horror) and Contagious (Sci-Fi/Thriller):  These can almost stand alone on their own (in order).  You really don't need any knowledge from any of his other books to enjoy them.
• Rookie/Starter, and the remaining GFL books (Sci-Fi/Sports/mob): Again, these can almost stand alone on their own (in order of course).  Having exposure to Infected and Contagious would be nice, but not necessary.
• Crypt (Sci-Fi/Thriller/Horror/military): Again, these can almost stand alone on their own (any order).  
• Title Fight: I'm sorry to say <GASP> that I haven't heard this one yet... shame on me.  Junkies, please help...
• The Tank (sc-fi/thriller): Again, these can almost stand alone on their own.  

-Sci-FiGeek Version 2.0 - Bigger, better, stronger... and with improved green goo!

I almost wish there was a "Siglerverse primer" out there, that junkies could pass along to the uninitiated. Recommending any of these works tends to have me expounding on the Purist/League conflict, the Take-Over, and so on. Not that I mind, of course... but it'd make my job as a pusher much easier if I had a smack-sampler!

... so Scott, you haven't heard Title Fight?! I would think you'd need to before The Starter hits.

-Chris Toohey
Blogger : Podcaster : Geek
http://www.twitter.com/ChrisToohey

And now that I have the missing first two episodes, I'll be jumping into in a few days.  Definitely have to get it in ASAP... 

-Sci-FiGeek Version 2.0 - Bigger, better, stronger... and with improved green goo!