All depends on the budget
The above suggestion is an excellent one.
1) Canon 60D + 15-85mm + 55-250mm or 70-300mm. Add 50mm f1.8 for low light.
15-85mm is very convenient walk-around lens touching extra wide-angle and mid-tele portrait range. It has got excellent reviews but a bit expensive.
55-250 is top value for the money.
70-300 is again very good but expensive.
50mm is the cheapest steal.
2) I am using Canon 550D + Sigma 10-20mm f4-5.6 and Tamron 28-75mm f2.8. Tele is 55-250 and another low light is ofcourse 50mm f1.8.
I bought Sigma and Tamron as they are much cheaper than Canon 10-22 (half the price around $430) and 24-70 or 24-105 (1/3 of the price around $400) but still match up with Canon lenses around 90%. Tamron infact touches the image quality of the big 2 neck in neck.
3) If u want to get one or 2 lenses at the moment then try 18-135mm with 50mm f1.8
Canon 60D comes in kit of 18-135mm so this combination should come with Canon discount.
This lens is best economical walk-around for Canon. I don't like 18-200 as its very soft at tele-end.
4) For prime lovers, 24 f2.8, 28 f2.8, 50 f1.8 and 85 f1.8.
These are all cheap lenses with 85mm touching $350-400. Just in case u know
But whatever lens combination u purchase, this time start above kit lens