Nellie, I would recommend you do a face to face. Your email could be construed as spam. You might pop in to open houses on the weekend. If the realtor is busy, do not disturb, but take a business card or flyer from the counter. Call during the week and make an appointment for coffee, or to meet in their conference room, not at their desk where they can be interrupted.
Another approach would be to attend the listing meetings. Most of them are early morning and open to "outsiders". There you may have the opportunity to meet other business people, i.e. insurance, escrow and title, builders, etc. This will give you a chance to look them over and see who you might like to meet and persue a relationship. Again, instead of leaving your information, pick up info for those you might like to meet and give them a call.
In these approaches, you are not interrupting, but seeking permission to approach them. It seems like a slower method. It will be more productive in the long run and you only need 1 or 2 new clients to get started. From there, you can ask for referrals. You can use the same approach for financial planners.
Best to you,