At Crochet Me, you can send private messages to other users. Think of it as an internal email sort of thing. Click "My message" in the "My Crochet Me" block on the far right. (This screen is where you would go to read your messages.) To send a message, click "Write a new message".
To: Either choose one of your buddies from the "Contacts" list, or simply begin to type the name of the user to whom you wish to write a message. As you type, usernames will begin to show up (sometimes after a short pause), at which point you can simply choose the one you're looking for from the list.
Subject: Type a subject, as you would when writing an email message.
Message: Type your message here. You may use the simple formatting on the toolbar above the text area.
When you're finished, click "Send private message" to send the message. Or, you may click "Preview" to view (and possibly make changes to) the message, but you still have to click "Send private message" when you're finished previewing it to send the message.