How do I use /tp to tp a player to a mob with a name

Use the name argument in the selector:

/tp @p @e[type=Zombie,name=David]

You can summon in a named zombie like this:

/summon Zombie ~ ~ ~ {CustomName:"David"}

Or rename a zombie egg in an anvil then use it.

For multiple teleportations I would use the following command:

/summon Arrow ~ ~1 ~ {CustomName:"Tp Location",CustomNameVisible:1,inGround:1,pickup:2,life:-9999}

This summons a near infinitely lasting arrow that is called "Tp Location", you can change that to whatever you want, eg spawn, home, starship, endportal, what ever you feel is appropriate.

Then you simply do the command:

/tp @p @e[type=Arrow,name=Tp Location]

This teleports you to that arrow, and you can not be teleported to any other arrow as they can not be named without command.

Just don't name the arrows the same things, eg "home" and "home", as it won't work.

And don't tp to the arrows in creative as they get picked up, used as a fast removal method.

You can also make the player remove the arrow by doing:

/execute @p ~ ~ ~ /kill @e[type=Arrow,name=TP NAME]

This makes it possible to make one way tp points.

I have tested this in 1.9.4, and no other versions, if it doesn't work then it is because you are in a different version of Minecraft.

TL;DR: Use named arrows.