When should I send out Save the Dates and Invitations?

If you're having a local wedding on a nonholiday weekend, it is not necessary to send out save-the-date cards. Instead, just send the invitations out about six weeks before your wedding date. For a wedding taking place on a long weekend—which is often centered around a holiday—save-the-date cards are a great idea because people tend to make special plans early for these weekends. If you are having alot of out of town guests it is also a good idea to send out save the dates so they may begin making travel plans. Drop save-the-dates in the mail about five months before your big day. Save-the-dates have become more popular with todays brides.
Invitations for a long-weekend or holiday wedding should be mailed out a little bit earlier, as well. (Aim for about two months in advance.) If you're planning a destination wedding, your save-the-date mailing should go out about 9-12 months prior to the wedding. This gives guests plenty of time to make travel arrangements and to plan to take extra time off from work if they want to stretch your wedding into a vacation of their own. The actual invitations for your far-away fling should be sent 2 ½-3 months prior to saying "I do."
You can find beautiful modern wedding invitation designs at Swanky Chicks! We also work one on one with our brides to create custom couture wedding invitations.

source: Brides.com