What are Some Ways To Promote a online Business in a low budget?

Tell your friends to tell their friends.
Give something away in a lead exchange.
Have a contest to win something.

What I suggest don't go for multiple ways cause if you do multiple ways you will be frustrated try one ways for one month and be expert on that and move to the next way..this is how the marketing ways works..

I recommend you to start with article marketing...

Let me know if you have more questions..

Thanks
Alam

Facebook - is viral! make a fan page and use-it. if you don't know how check this: The Social Networking Academy

article marketing
join forum and become active in threads
submit press release
social bookmarking
blog commenting
...all these things are free.

hey, if your building on a budget try ezine solo adverts, they always work pretty well, although you will have to write pretty decent adverts, but you can get a lot of bang for your buck.

Of course videos and articles are great as you can get ranked in the search engines but also sites like ezinearticles.com and Youtube have tons of traffic coming there way anyway.

Best of luck

Many ways but what is your niche? Different ways may suit different niches.

Depends on what your online business is.

I see a lot of people with laptops at starbucks every day and every startbucks has a bulletin board for locals to post up anything they want. Could be a good opportunity for a CPA offer.

And keeping to offline marketing, there is always printing up little flyers, going to the bookstore and sticking them in all of the books having to do with your niche. That is targeted traffic.

1. Build diverse unique onsite content useful for your target
viewers. Diverse = articles, repurposed to become an ebook or a report,
repurposed to become a Microsoft PowerPoint presentation, repurposed to
become a Flash video, and blog post with commentaries about syndicated
articles, all posted on your site under your supplemental article resource
section, supplemental ebook or report resource section, supplemental
presentation resource section, supplemental video resource section and
supplemental blog resource section. Unique = Content integrated with a
niche expert's own relevant set of observations, inferences, actual
experience, test results, theories, opinions and perspectives. Useful =
Content aimed at providing your specific target audience benefits in the
form of info, strategies, tips, techniques and advice. Unique = Content
written in a style and packaged in ways not found elsewhere...

2. Update your sitemap.xml and robots.txt then submit it to Google
Webmaster Tools...

3. Syndicate your articles, ebooks/reports, MS PPT presentations and
videos to article directories, ebook/report repositories, document-sharing
sites and video directories where a lot of webmasters targeting audiences
with needs and problems similar to the needs and problems of your target
viewers go to take content for syndication on their sites...

4. Update your FaceBook Fan page with posts informing your target
audience about your onsite and offsite content...

5. Twit about your onsite and offsite content...

6. Social bookmark your onsite and offsite content pages...

7. Submit your onsite and offsite content pages to RSS directories...

8. Google each of your target keywords...

9. Pinpoint top ranking contextually relevant pages allowing content
contributions from viewers as well as promoting discussions among
viewers. Build your reputation in those online places as a friendly expert
resource of useful, contextually relevant information, tips, strategies,
techniques and advice...

10. Contact webmasters with websites heavily trafficked by your target
audience as well as webmasters with large mailing list of subscribers
included in your target audience. Negotiate content contributions with
details of your business/website and links pointing to supplemental onsite
content pages as well as email solo ads and other mutually beneficial joint
venture deals...

video marketing...free...quick....google loves top sites like youtube (not unlikely for videos to get ranked on the first page of google very quickly).....create videos and syndicate them to top video hosting sites....make sure you have your link in your video

I would do:
-SEO: there is a lot of free info about it
-Article Marketing: look up ArticlePrince's plan as well as others
-Video Marketing: make popular youtube videos and post a link to your business

There is already lots of great ideas listed. And I didn't want to repeat any. There is one I didn't see though and that was Press Releases.

Press Releases are good for nearly all niches. Plus with a PR you can be a little more "salesy" than a normal article. This can help get backlinks and some decent traffic as well as the PR might rank high in Google also.

Hope this helps, Good Luck

Write guest posts.

A quick answer - social marketing. Very quick viral way to spread the word!