I'm a salesman by trade (have been for the last decade). I both solicit and am solicited, a lot.
I can't speak for everyone and every business (it certainly makes a difference the type of business you are soliciting) but:
Cold calling sucks, but it works. Also, before you think outsourcing it is a good idea, consider how much training will need to go into the new employee. Most will also hate it, realize it sucks, and move on. The turn-over rate is rediculous in this field. Also, no one will work as hard for a sale as you will. I promise. So if you have a limited number of phone leads to call on, it's best to do it yourself. If you've got a bottomless pit and the patients to train these people, then by all means outsource.
I get about a hundred business emails a day, including solicitations. Most I don't even read past the first sentence before I delete it. If I do make it past the first sentence, it's only because I thought the copy was good and wanted to see how they were marketing what ever they were selling. I cannot remember the last time I made a business purchase because of an email I've gotten. Also, the converse is true - I cannot remember the last sale I've gotten solely because of an email, but I do use them to verify a contact exists before I spend time cold calling them (if the email bounces I don't bother til I'm absolutely out of leads) and to use as something to reference (I'm a fan of being as familiar with them as possible even on a cold call, uses the email as the excuse for my call and acting like they in fact wanted my solicitation in the first place. most people don't remember right away if they did or didn't, which lets me get past that initial guard people put up when a stranger is on the phone).
Those thinking about faxing - don't. While about once or twice a month I'll catch one on the machine after I print something out, most of them don't even make it past my secretary, and she has never, ever, passed along information from them except for the local deli which sends out lunch specials every now and again and caters our meetings. So unless you have a similar business which would cater to secretaries (she arranges the lunches for meetings, and the faxes make it easy for her to give us a list of what to pick from to eat), don't bother.
The door to door approach can work, especially if you are targetting residential (if someone comes into my place of business trying to sell something I rarely talk with them, but they very often are able to bypass me and go straight to purchasing or our project planner and at least get their ear for a minute or two, especially if they start by making small talk with the girl who works the front desk). We have responded positively to a few of these calls (our freight carrier and electrical panels come from people who started off by just walking through our door).
I realize every business is different, so I should preface this with the fact that we sell very expensive (100k is around the smallest order) products, and the above may not be true for all businesses. I'm sure email works great for people pushing products to those on DP, WF, and even here. And I'd venture a guess that cold calling would in fact be LESS effective for that same group of people then a well worded email.
I'm certain if you go into more detail about what exactly it is you do you'll get more constructive feedback on how to reach customers.
