How to get into voiceover work
An excellent way to break into voiceover work, is with student films. This sector will allow you the opportunity on a less stressful scale, to experience what the audition and recording process is like. Going into a recording booth for the first time, is quite an experience. For some it can be an adjustment. But keep focused and breathe. Working with students will allow you the chance to do several takes, listen to all your playbacks, make adjustments, and take breaks. Since students are more flexible and their recording studio schedule often lasts for 2-3 hours. Always ask for pointers, from the director about how they would like the voice work to be done. The more information you have on the pace, pitch and tone for the role/advert, the better. You can even ask, between takes how the recording is sounding. They will be more than happy to clue you in. Listen carefully to your playbacks. Especially for the "popping P" sound. And the depth of your breathing. And the consistency of your voice. Especially if you are doing a voice that is an animated character or an accent (not your on natural voice). Remember the microphone is always "on" and recording you, once you're in the booth. So be careful of what you say even under your breath.
After gaining experience with student work and more confidence in this area you might want to approach not-for-profit organisations that use radio to broadcast their campaigns or jingles. Hospitals or community centres would be a start. However, there would be no pay for this sort of work.
When you have amassed enough work for a demo showreel (your voice with varied samples) research the persons that book voice artists for ad agencies, A/V production companies and especially radio stations. Send the showreel along with a covering letter (do not expect these sources to return the sample). It would be a good idea to label your CD with your picture, name and contact information, list the different voices on the recording and the date that you submitted it. As an alternative, there are online audio recording sites that are free of charge. Soundcloud.com is an example. You can record as many samples as you like on their site. And use these samples to send to prospective clients. After you submit your sample, make contact in one or two weeks, requesting an audition or meeting.
If you're lucky, you will be invited to the company's office or studio to read. Or they might email you a script and ask you to record it and send it back via email.
If you are cast, you'll be invited for a voice test. Many people are involved in the production, make sure you make a good impression, with each of them. Since you will be called on again, even on short notice to do more work, for having the talent, professionalism and ability to record in the time slot allocated. Being on time with the recording is most important, since studio recording time is quite costly. And going over that time is unacceptable.
There are specialist agents for voiceover work. Research them in "The Actors Yearbook" (an annually published book, available at the public library). Albeit, it is difficult to get representation. These agents are very selective and handle a small and well cared for list of artist. Look them up on line, and note the clients that they represent. The best way to be considered is to offer a talent/voice that fills a gap.