Does your filter have a little spray bar attachment (plastic tubes that you stick together and fit onto part of the filter - not exactly the greatest description!), just wondering if that is what you mean by different attachments.
You can use the airpump and an airstone at the opposite end of the tank, airstones cost about 75=95c here for a basic small one and silicon clear or coloured tubing about $1 a meter (may be less over there).
What size tank do you have?
Two weeks isn't enuf time to cycle the tank. It can take anywhere from 4-8 weeks. And as we're heading into summer, no doubt you're starting to get some warmer weather, might be better if you wait till it's cycled.
For cycling, if you don't yet have any, buy freshwater test kits for ammonia, nitrite and nitrate. You can buy them separately for approx $15 ea (may be less in Oz) or about $50-75 for a full kit "Freshwater Master test kit" that tests ammonia, nitrite, nitrate, low ph, high range ph. The most important things to monitor while your tank is cycling is ammonia, nitrite and nitrate.
Apart from a dechlorinator, water ager or water conditioner you do not need any other chemicals for your tank (ie: no ammolock, no ph up or ph downs or so called bacteria boosters).
Have you seen this site:
www.axolotl.org
Also, what substrate will be used for the tank? Try not to use gravel as it can cause blockages and other problems and takes months to come out if they manage to poo it out. You could always have a bare tank floor, sand (which can be purchased cheaper at Bunnings or other type hardware/landscaping store)or large pieces of slate or rock.
And I don't think you'll mess up! At least you're researching before you get your daughter's axie.