When I login I have been teleported away from home. I get this message, "Your desired location is .

[LLynn Zeplin]

When I login I have been teleported away from home.  I get this message, "Your desired location is not currently availble.  You have been moved into a nearby region."

[Rolig Loon]

Yup, that will always happen if your home region is temporarily unavailable.  The alternative is to not let you log in at all, which would probably annoy you even more.  Your sim may be down for unscheduled maintenance, or it may have too many people on it right now.  (Check the map view to see if there are loads of green dots.)  Try teleporting to a nearby sim and either walking or flying into yours to see if it is off line.  If it is, wait a bit to see if it clears up.  If it's still offline in a couple of hours, submit a support case with the category Land & Region >>> Report a Region Off Line.  LL usually responds to that category of report within about 20 minutes.