Although this is a Sand team, I'll go over the teambuilding process because my original intention wasn't a weather team.  The team began as a combinaton of Imprison Misdreavus and Scarf Gothita because Imprison Misdreavus is crazy fun and it turns Porygon into a worthless switch-in.  Now now, I know you may be thinking that Missy is dead weight if the opponent isn't running a Porygon, but it's still a 19 Spe, 18 Spatk threat.  However, because I wasn't running Dazzling Gleam, I needed a decent Fighting-type check and Gothita is just a really cool Pokemon.  Scarfed Psychic is a threat to pretty much anything that doesn't resist it / is immune to it and there's a reason for coverage moves.  The main problem with this core was its weakness to Dark-type moves, Knock Off specifically, so Acrobatics Mienfoo was added to capitalize on switching into Knock Offs.  From this point, I felt the team could use a main goal or idea so it wasn't just a bunch of cool Pokemon thrown together without any synergy; thus, the Sand core was born.  Hippopotas is the obvious choice for a Sand setter and is actually a great defensive wall.  Whirlwind is included because Misdreavus will commonly switch in and try to take advantage of Hippopotas with Nasty Plot or Substitute, but Hippo don't give a fuck, it blows shit away.  This also makes it a nice "Revenge Killer" for boosting Pokemon like Scraggy or Fletchling, as it can take a +1 Physical move and proceed to Whirlwind the opposing Pokemon away.  Of course, with the inclusion of Sand, I had to have a Pokemon to take advantage of the weather.  My first choice was Life Orb Drilbur, and it worked pretty well but it lacked the power with Shadow Claw to KO Missy.  My next choice was Sandshrew, and after finding out it could learn Knock Off, I fell in love <3.  To round off the team, Endure + Recycle Magnemite was chosen to handle Chinchou and Fletchling and get me out of some sticky situations by constantly healing itself.  The team itself is rather balanced, and can apply some offensive pressure and take some hits at the same time.  It has some unique sets which might seem inferior, but once you play around with the team you'll notice that everything works pretty well together.