I bottled for 10 years before making the switch last month. The only reason I switched is wrist tendonitis. Kegging is definitely easier but, bottling wasn't so bad either. One down side of kegging is the initial cost. And, as with most things in homebrewing, there is a wide variety of equipment to choose from and the only real limitation is your bank account.
Because it's fresh in my mind and I still have my notes, I'll list out what I bought and why.
New 5 lb CO2 cylinder: $80 (LHBS)
CO2 refill: $15
I only considered new kegs because both local places I checked refill the tank you bring in and do not do exchanges. If you buy used you need to make sure it has been tested recently or pay to have it done.
3-dial Taprite regulator: $112 (Kegerator.com)
I went with Taprite brand base on recommendations for multiple brewers on this forum. I went with a 3-dial (2 for serving kegs; 1 for CO2 tank) so I can serve beers at different pressures or use one for serving and the other for force carbonating. Going with the 3-dial vs the 2-dial was definitely an optional upgrade.
(4) Used kegs: $228 (MoreBeer.com)
I had originally only planned on buying 2 but, went for 4 because More Beer had a set of 4 for $280 and I had a 20% off coupon. That brought the price per keg down to $56 each. They aren't pretty but, I'm the only one who will be seeing them. They sent two replacement poppets to replaces ones that leaked. Plus one keg had some syrup stuck on the inside wall that I had to scrub off.
(2) Picnic Tap 2.1: $27 each (WilliamsBrewing.com)
Think of these as picnic taps without the hose. I picked these for ease of serving and to avoid potential problems some homebrewers have with getting the line length correct to avoid foaming. This also allowed me to skip buying/building a kegerator/keezer.
(2) Floating dip tubes: $25 each (WilliamsBrewing.com)
Definitely a "want" item and not needed. Normal dip tubes that came with kegs would have been fine.
(1) 3 port gas manifold: $30 (LHBS)
This allows me to server multiple kegs off one regulator.
(6) gas & liquid disconnects: $6 each (LHBS)
12' gas line hosing: $??
I could definitely gone kegging for less but, I hope this helps you with ballpark costs.