Looks like you are in Alabama. What is your ground like? What size water line? How far in the building do want to run it?
If you are running a 1" or 3/4" line it should be fairly simple to run this under the slab into the building. It will take some accurate measuring and a little work but it is doable.
Select the location where you want the line to come up into the slab. The closer to the edge of the building without being where the footer is the better.
Make a hole in the slab only as large as needed. You can core drill it if you have or can rent the tools or you can cut a hole with a saw that has the proper blade. Of course a cut hole will be more square, but it can be large enough to put your hands into.
Dig the dirt out of the hole deeper than what the pipe depth should be, about 6"-8" deeper then the slab - straight down, do not undermine the slab.
From the outside dig a trench from the building straight out at 90 degrees so that it lines up with the hole inside. Make it about 2" deeper then the slab. Make sure the bottom of the trench is level. Using a pipe that is large enough for the water line to pass through as a sleeve. If you are using a 3/4" waterline you will need 1 1/4" schedule 40 PVC or 1" 'thin-wall' PVC - irrigation pipe (they sell it in Home Depot and Lowes)
With a hammer (a "mini-sledge" works good) tap the sleeve pipe under the slab, stopping after a few inches, pulling the sleeve out and shaking the dirt out. You will have to tap and pull several times. The sleeve should arrive in the inside hole with space above and below it in the hole you made. If you measure the distance you need to go before you start tapping, you will know when you should be there.
Cut the sleeve or pull it back so that the end inside the building is just at the edge of the hole. (This is for PVC) Put you waterline through it and go inside and glue a 90 on the end of the pipe. You will find that if you aim the 90 down it will keep it clean while you glue it on, then rotate it so it faces up. Glue a piece into the 90 longer then you need - you can cut it off later.
Now, go outside and run the pipe to the source however deep you need it to stay below a freeze line if you have one - we don;t have to worry about that here. After you connect the line to the source, flush it with water before you finish connecting it inside to clear any dirt out that may have gotten in it.
Fill and pack the dirt back into the hole. If you don't want the dirt hole in the slab, fill it with "redi-mix/quick-crete" and smooth it out. If you make the hole only as large as you need it to work, it will only take one bag.
If you need to go a distance under the slab you can always "jet" the sleeve or waterline under the slab. I would not dig or tunnel under the slab because the more dirt you pull out from under the slab, the weaker that spot/area will be since you will not be able to pack the dirt back in as tight as it was.
