Someone in a new situation is usually excited and enjoys recognition, whether it's a new neighborhood or a new job. By sending a welcoming letter, you are offering a friendly hand and opening the door to a future business relationship.
1234, Main Street
Boston, MA 02123
08 April, 2005
<Recipient Address Goes Here>
Congratulations <on new situation>. A change is always exciting, but it usually comes with a lot of unanswered questions.
<Your introduction.> This is simply a short note to introduce <myself/ourselves>. If <I/we> can be of service (in any area), please don't hesitate to call <me/us> at <phone number>.
If <I/we> don't hear from you, I'll give you a call in a few weeks, after you've had time to settle in. Best of luck!
encl: <List of enclosed items goes here>