Emailing is just one part of business and marketing and I'll be honest with you, I hate spam too. I'm sure you do also.
I suggest thinking about this as a whole package for getting yourself out there:
1. Good website with a domain name that fits your company name.
2. Facebook
3. Email that uses your website domain name
4. Good phone contact
5. Newspaper advertising. It's not as popular as it used to be but it still works. Especially since much of your competition doesn't advertise in it as much as they used to. If you don't have a large budget buy a regular classified ad so it keeps your name out there when someone does need a
sign/banner/etc.
Take pictures of your work that you believe represent your best work. Then post them to your site and use them on your Facebook page. Then link them together.
6. Have regular business hours. Don't be in business if you aren't going to answer the phone. Even if you have to have a phone answering service. People like to talk to someone. Then return phone calls ASAP.
7. EDDM Postcards. This is huge nowadays. I highly recommend this because it can be substantial. Most people don't realize they can mail for 17.5 cents (in the US) each, and without paying for addressing. Find the area you want to target and mail to everyone/business. Be sure the card is professional. Don't cheap out on design or good printing. So far this year I've printed 60,000+ postcards just for our local hospital regularly sending out health information. They love the option of hitting everyone in this small county.
Put this altogether and people will be coming to you. No spam at all. Don't forget to be very courteous and nice. Building relationships is the best way to get and keep business. Then you won't be able to keep up on answering all the emails of people needing quality work.