I'm afraid some churches can be this way - although they shouldn't be (and often they don't even realize they are this way). One reason I wanted to reprint your letter is because I hope it will remind church members to be more welcoming to visitors. The Bible says, "Remember to welcome strangers, because some who have done this have welcomed angels without knowing it" (Hebrews 13:2, NCV).
The first question you should face is this: What is God's will for you concerning this church? Don't turn away from it just because you haven't found the people as warm and friendly as you'd hoped. Perhaps God has put you there because He wants to use you to help them break out of their old ways of doing things.
The second thing you need to consider, however, is this: Can you grow spiritually in this church? Will you grow closer to Christ, and find out more about His will for your life? Is the Word of God taught clearly and fully? Are prayer and worship important, as well as service to others?
Pray for your pastor, and for this church's leaders. A church like this will die in a generation or so if it doesn't change - and God may have put you there to help them see this. A church is more than a social club; it's a place for God's people to grow closer to Christ - and to each other.