One of the first things people claim to be stopping them from starting their own freelancing career is that they don't have a group.
From my experience, the most difficult thing about getting a group going is finding people that you want to work with that will make the initial investment of time to get the group started. Classical musicians in particular tend to be extremely defensive of their time and would rather spend it playing 6 bars of Beethoven by themselves in a practice room all day. Most people I know don't want to show up to rehearse something unless they're getting paid to do it that weekend and I know from experience that the best way around this is to make the group exist on paper when starting out.
If you're willing to do all of the legwork yourself, you can get a group going with just an hour of time from everyone else. Let's say you've got a wind quintet and you are looking to play some graduation ceremonies. All you really need from other people is an hour of their time to sit down and read some music down and record it. Assuming that you're bringing in solid players that can just sit and play, you'll have more than enough quality audio to get your group started.
Once you've got a recording, no one else has to do anything if they don't want to until you get a gig. Here are the steps you'll need to take and some free resources to help you do it.
Make an audio sample.
There are tons of programs out there for this. Personally, I use Audacity because it's free and really easy to use. Realistically, most people aren't going to listen very long (if at all) so make it short and sweet. Attach it to all of the emails you send to potential clients to make it easier for them.
Set up a website.
There are countless places on the web that you can create webpages for free. Here are few that I've used or know that other have used and had positive experiences with:
Weebly---I found this to be by far the easiest to use. Very simple, clean, and easy design.
Wix---Wix is a much more involved website design platform. It has a lot more bells and whistles in the free version than Weebly, but this also makes it a bit more to manage for a first time user. Still a great website though.
Wordpress.com (.org is different, so be aware of that)---I know many people that host their blogs through Wordpress and have had great experiences with it. I had difficulty figuring out .org, but .com is apparently easier.
All of these basic website designers come with more than enough gadgets for what you'll need to get started. Realistically you will only need a place on the page to talk about the group and what you do, a page where your sound sample is available, and a contact form. These are all standard features and they're all you really need to get started.
I know what you're thinking, that sounds like an incredibly boring website. But I'm a firm believer that simple is better. This is especially true when starting out.
However, I know that it's nice to have some photos, visitors, domains, and all that fancy stuff, so here are a few more links you may interested in to make your page better:
istockphoto.com---Here you will find thousands of images that are free to use. There a some really great pictures here of EVERYTHING so this is a good place to start when filling space on a webpage.
gettyimages.com---This site has some free images, but most are for purchase.
soundcloud.com---Host your audio files here if you like.
domainsinseconds.com---Buy your own domain name here! Or at Godaddy.com There are tons of places to do this. It just adds legitimacy to your site. (Free sites will usually have the host in the name)
http://tools.seobook.com/---If you want people to actually find your site when they're looking for the services you offer, check out this website. Search Engine Optimization (SEO) is important so that your page pops up on Google and other search engines. Here is help from Google themselves: google.com/websiteoptimizer
If down the road you want to get a logo for your group/organization, the following resources are all fantastic crowd sourcing sites that allow you to put up a description of what you want and have thousands of freelancers all over the world have a chance to design it for you. You just name the price, what you're looking for, and time limit, and the designs will pour in. This also works for merchandise, websites, brochures, and just about anything else!
This will take an afternoon to set up, but once you get it up and running your group will officially look as legitimate and professional as any other group out there!