The Sisters are currently in the middle of a reboot of the line. There are rumors that they will be getting a line of new plastic models soon, which is good because the old pewter ones are becoming prohibitively expensive. They also were recently issued a pared-down version of their codex in White Dwarf. The new list is easier to use, but some players felt that many of their favorite rules and abilities were lost.
There is currently no starter box, but a decent starting force might look like this:
10 Sisters of Battle with superior and two special weapons
5 Dominions with superior and two special weapons
This bare bones army will run you $150.85 retail. Don't pay this! Get online and find some sisters for a discount. Once you have a core force, go back to the store and buy the special weapons that you need to field some different kinds of troops. This will save you significant cash.
The army is generally depicted in Black, White, and Red. Pick a combo that you like and keep it consistent throughout the army. Paint the tanks the opposite of the troops by way of contrast. If you are painting lots of white, get a tutorial somewhere because it will drive you crazy without the right techniques!
- You will need an HQ. The Canoness will support your troops by increasing their ability to succeed at acts of faith. St. Celestine is very durable and pretty good as an assault force on her own. The Confessor and his warband can also do well as an assault force.
- Focus on getting more sisters mounted in Rhinos. The army can field a lot of 3+ armor saves and shoots as well as Space Marines. The basic troop choice is a solid value
- Do what you can to increase your long range firepower. Retributors can field four heavy bolters or multi-meltas and the Exorcist tank is a beast.
- The army has access to quite a few specialized close combat units. Take a look at them, particularly the Penitent Engine.
I believe that the Sisters of Battle are one of the most aesthetically pleasing armies out there. The models are very nice and the tanks can easily be modeled to look like rolling shrines. The army will benefit from a full codex and some new models, however. Since the army has a lot of specialist troops, they will need to rely on one another pretty heavily. Keep your shooty models shooting and get your close combat models in as soon as possible to protect the weaker sisters. Finally, don't forget the Acts of Faith!