Andrew Brehaut writes about Clojure, covering web stacks, state monads and parsing, and his move from Python.
Commenters call his Ring introduction the best overview of the Clojure web stack and a 'motherlode', and recommend it to newcomers.
If you're referring to core.async specifically, keep in mind it's very new. Its readme[1] goes as far as to say, "This library is work-in-progress, experimental, broken etc. It should only be used by people working on it, ATM." With more maturity will surely come more examples and tutorials.
But if you mean Clojure(Script) in general, I kind of agree. There are some beginner friendly tutorials; lately Andrew Brehaut's intro to the Clojure web stack[2] has been smooth going for me, despite being a bit dated. But you have to look around. In particular, I've found the small-scale mechanics of the language easy to pick up via Clojure Koans[3], 4clojure[4], and ClojureDocs[5]. What's missing the most IMHO is approachable introductions to the big-picture concepts. Especially the less generically lispy, more Clojure-specific parts, concerned with concurrency and state. (I hear the book Clojure Programming by Emerick et al. is good for that... have yet to read.)
I kind of understand Clojure not being easy or quick to learn, because powerful tools take time to master. But even with that said, it could be better. When I get confident with Clojure I hope to be part of a new wave of Clojurists who write really beginner-friendly tutorials :) I think it won't be the "gurus" who write them, but regular joes/janes like you and me for whom the initial difficulty of this stuff is still a fresh memory.
[1] https://github.com/clojure/core.async
[2]…
One of my favorite resources is the #clojure tag on Twitter. I use Tweetie and have bookmarked a search on that.
Here are a few sites from my GReader
http://www.bestinclass.dk/blog.html
http://nakkaya.com/
http://freegeek.in/blog/
https://groups.google.com/group/clojure
And here are a few tabs that I currently have open (Maybe this weekend I will get to them :D)
https://github.com/dbushenko/ClojureBlog
http://skillsmatter.com/podcast/scala/talk-by-patrick-fredriksson
http://brehaut.net/blog/2011/ring_introduction
http://www.codequarterly.com/2011/rich-hickey/ (Interview with Rich)
http://news.ycombinator.com/item?id=2682191
http://news.ycombinator.com/item?id=2709319
Hope these help :)
The obvious reason for no Object/Relational Mappers in Clojure is that while Clojure has objects available, it doesn't orient around them. It makes much more sense to treat a set of records from the DB as a sequence of maps.
For DBs and Clojure in general I can only speak about CouchDB via Clutch and SQL via ClojureQL and clojure.contrib.SQL. I don't want to claim to be an expert in either of these technologies, but if you have some more specific questions i'm happy to do my best to answer them. you might find some answers about couch in an older post of mine http://brehaut.net/blog/2010/couch_impedance
This is probably the best overview out there: http://brehaut.net/blog/2011/ring_introduction, though it doesn't mention the new kid on the block, Noir (http://www.webnoir.org/)
Recently posted in HN, the Clojure web stack:
http://brehaut.net/blog/2011/ring_introduction
The source of that quote is a nice read: http://brehaut.net/blog/2010/on_iteration