You ask a very good question, and one that I get from many candidates with whom I work. Seeking admission to another state bar on motion can be complicated, time consuming and quite confusing. Until recently, attorneys struggled to find accurate information on the process. Thankfully, much of this information is now on the Internet, and to the extent that an attorney has specific questions regarding the process as it applies to his or her situation, most of the state bars have qualified employees available to answer such questions. As a legal recruiter, I tell every candidate seeking admission to another state bar to research the applicable rules online and then call the bar and speak to a live person. The rules for each state differ and many have changed recently (Illinois, in particular, amended Rule 705 of the Illinois Supreme Court Rules in January 2011 to make admission on motion easier on attorneys like you), so it may be next to impossible to locate information specific to each attorney's circumstances and situation.
In my professional experience, the only times I have seen attorneys run into trouble seeking admission to another state bar on motion arises when the attorney does not have all of the necessary information to determine: (1) if they are actually qualified to waive in; (2) what is required (in terms of paperwork and other supporting information) of an attorney who is qualified to waive in; and (3) how long the process generally takes. The last thing anyone interviewing with a law firm wants to do is to provide inaccurate information on his or her eligibility to waive into a state bar on a job interview or shortly after being hired. Obviously, doing so will make the candidate look ill-prepared and less-than-serious about making the geographic move to that state.
To help you get started, here is a link to a list of all 50 state bar websites: http://www.nextclient.com/resources/legal-links/state-bar-websites/. I wish you nothing but success with your job search and move.