You only need to hire an expensive lawyer, IF there is "a lot of money or a large estate involved", or there are complicated child support or alimony issues. Otherwise save your pennies. Most "family law" attorneys charge scheduled fees as dictated by the Law Society, so there will be little difference in cost, if any between an inexperienced or middle of the road attorney. The key of couse is experience. Many lawyers will take a stab at Family Law, but many are out of their depth when the going gets tough, and are likely to enlist the help of an experienced firm to help them through it should that occur. Of course, a downtown reputable firm will charge a hefty premium for that 20th Floor office, but they will tend to be more pushy, and require a larger retainer. A suburban firm is probably your best bet.
Expect to drop a $2000-3000 retainer before they even get going. If your case can be settled early and amicably, your total cost will be in the $5,000-$7,500 range. If it goes to trial, expect to pay $30,000 for a straightforward divorce, and $50,000 for a complicated one. Of course, if the estate is sizeable, and you need a team of lawyers and their articling researchers, then you could top out in the $100,000-$150,000 range.
For a general description of the processes involved, read up the DIY guides published by the Self-Counsel Press. You can pick up a copy at London Drugs for about $25. It will give you an excellent overview before you get your feet wet, and if your situation is fairly benign, and both parties are cooperative, you could save a bundle, by filing it yourself for less than a thousand.