Getting around the Lake Baikal area takes some patience, but it's by no means impossible. Don't show up hoping to keep a tight schedule -- you never know when boats or buses are going to be delayed or cancelled outright. If being told that "Oh, your boat doesn't run on the 2nd Tuesday of every third month" makes you angry, this is probably not the place for you! But that being said, there really are plenty of transportation options that aren't that hard to navigate if you know a little Russian. Take the time before you go to at least learn the Cyrillic alphabet and some basic pleasantries in Russian, and transportation will become a lot easier.
The closest major city to Lake Baikal is Irkutsk, and probably where you will arrive and possibly sleep. There is an airport here that has quite comfortable flights from other major cities in Eastern Europe, although don't be surprised when you step of the airplane and find yourself standing in the middle of the street outside of the airport. Taxi drivers may even start offering their services to you before you've fully disembarked! You'll find plenty of taxis by the train station and airport, although sometimes they are hard to find elsewhere. Haggle over the price before you get in the taxi. It should never cost you more than a few dollars.
Once you're in the center of town, much of Irkutsk is fairly accessible on foot. Most streets have decent sidewalks, and there are quite a few parks for taking a break. For far off destinations, like the southern sea port, you'll want to catch a bus or marshrutka. A marshrutka is a privately run minivan that functions almost exactly like a bus, only a little more informally. Just wave one down, check the destination from the sign in the front window or ask the driver (I usually do both, just to be safe), get on, and pay the posted fee. When you get to where you want to be, holler at the driver to stop. It's not the best transportation option for really shy people, but they run much more frequently than buses and are often quicker too.
To get to Lake Baikal, you have a choice of a bus or a boat. Although the boats don't run that frequently, it's worth finding out the schedule and trying to make one of them. They're fairly modern little hydrofoils that speed down the river to the Lake through lovely, lush Siberian forest. The boat makes several stops, but the one where most tourists get off is Listvyanka, a small fishing village at the southern end of the lake. There isn't any local transportation around Listvyanka, but it's so small, you don't really need it. If you're one of the more adventurous types who wants to explore Lake Baikal even further, you'll have to find out about bus or marshrutka transportation that heads north along the lake. This can be infrequent, especially off-season (and be prepared for buses with no heat!).
Although no longer right on Lake Baikal, the towns on the eastern side of the lake also have a lot to offer, and can be easily reached from Irkutsk by an 8-hour overnight or day-time train ride along the Trans-Siberian railroad that follows the southern coast of the lake.
