Torn. Want to support LBS but they don't carry what I really want I live in a small town with one bike shop.  It is a good shop that I like a lot.  I am riding an bike that I built 15 years ago but I take it there and spend money on parts and maintenance.  I bought my kids 20" there.  When I can afford the bike I want to replace my bike I will almost certainly buy it from them.  But now I want to buy my elder son a 24" bike.  He is not a really powerful, aggressive rider.  The trails around here involve a lot of climbing.  I really think he would benefit from having a light bike.  There is one bike company that makes really light kids bikes (24" bike  &lt;20 pounds).  The lightest 24" bike from the LBS is closer to 27 pounds.  That is a pretty big difference for somebody that weighs 65 pounds.

I'm just curious about how other people feel about situations like this and what they might do.
I had the same problem with my current MTB - I talked to the guy at my favorite LBS (I have a number of specialist but large chain bike shops close by, hes a small operator), and told him what I wanted (He stocked the brand, not the model, and it was end of season so stocks were short supply). I had seen it on the internet for a significant discount, told him that. He made a few phone calls and said "I cannot get one, and even if I could, I could not get close to that price. I am more than happy to assemble it for you if you need (clearly he was meaning for a charge)". 

The LBS makes money from selling bikes, selling spares and servicing bikes. If you want to support your LBS, (as already suggested in the comments) ask him if he will order one in, and tell him what you have seen at what price. If he cannot or will not order a bike in, he should be more than happy to service it for you and will still sell you parts and accessories.