This is a great question. While there are a variety of factors that can impact the duration of your job search, generally speaking, you should expect your search to take between 4 and 6 months. Sometimes attorneys are placed more quickly, but it is important to set realistic expectations, so that you can best navigate the process and so that you don't get discouraged.
A number of factors can impact the duration of a job search. In some instances, a firm may be looking to hire very quickly. For example, a firm may have just hired a new partner with a book of business that needs to be staffed up, or the firm may have lost an associate that had essential expertise for current matters, or the firm may have just taken on a new matter that requires the firm to quickly obtain additional expertise on a particular subject matter or practice area. In these instances, the hiring process may move more quickly, sometimes taking less than two months from start to finish.
However, absent one of these scenarios, you can expect the search to take a bit longer. The current market is extremely competitive. Law firms are being inundated with resumes from qualified applicants and are often interviewing multiple candidates for one position. In some instances, prospective candidates are being put through three or more rounds of interviews. This is largely because firms recognize that candidates don't have as many options in 2011 as may have existed in years past and, as a result, are more comfortable taking their time during the hiring process to ensure that they hire the best possible candidate for their current needs.
Finally, keep in mind that, even after the interview process is concluded, it can still take time for a firm to make an offer. There are internal discussions to be had and references to be checked. And, of course, an offer needs to be prepared and conflicts need to be checked. All of these things add to the length of time it takes to secure a new position.
In summary, it is important to commit to your job search, but to do so with the understanding that this is a process. The key will be to set realistic expectations and to be patient, and to continue to perform at your highest level in your current job (so that you don't jeopardize your standing at your present firm). If you stay focused on your search, stay positive and optimistic and allow your recruiter to do his or her job to assist you and help create every opportunity for you, I am confident that you will be successful. Best of luck to you in your job search!