I'll throw my hat into the ring on this one by talking about some brands that people should look into. For what it's worth, my measurements are:
Often a hard thing to find for the tall, thin man. Someone mentioned either on this thread or on the www.styleforum.net/t/134832/rules-for-the-tall-and-skinny-man/
thread that European brands tend to work better, and I would agree.
H&M mediums fit quite well despite the lack of quality, but hey, a v-neck is a v-neck.
SNS Herning mediums. I am surprised no one has mentioned these. SNS sweaters are cut rather long, tend to have higher armholes, and are trim without being tight. I have like 5 or 6 of their sweaters.
You're effed. Go to a tailor, get some custom shirts made. I've tried and I've tried, but it just doesn't work. Occasionally a Brooks Bros. Extra Slim Fit shirt will work, but sometimes their sizing is inconsistent (i.e. I have one that fits great, and another that is pretty meh).
ZZegna's 38R Drop 8 model are usually cut a bit longer, as are a number of the more "fashion-y" Italian brands (Etro, Gucci, some of the Dolce).
Burberry Prorsum stuff is longer, and sometimes you will need to size up to a 40.
RLBL 40L seem to work well (although I find the jacket length a bit too long for my taste), and they make some 38L if you're closer to a 36 than 38 (the consensus is to size up when dealing with RLBL)
Phineas Cole does 38L, and it's really more of a 38R. The sleeves are unfinished so the tailors at Paul Stuart can extend a bit and then put on the buttons. This is helpful.
Shipley & Halmos 40R have sleeves cut on the longer side. Shipley tends to be a brand where people need to size up in suiting. Plus pants are separates so if you're waist is particularly small or large, this can be helpful.
Hugo Red Label 38R tend to have sleeves on the longer side with a trimmer fit than Hugo Black, but it's not perfect thru the body.
Epaulet Walt fit
Howard Yount trousers are tastefully slim
Gant Rugger makes pretty long, trim pants