I believe that prices of bonds are going to fall. Is there a mechanism
or vehicle for me as a retail investor to invest on my belief?

Hello.

First of all, I must note, as always, that Google Answers provides
general information, not professional investment advice.  If you need
professional investment advice, you should contact a qualified
investment advisor or financial planner.

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Yes, there are several ways you as a retail investor can profit from
falling bond prices.  These strategies include:
(1) short-selling bonds;
(2) short-selling exchange traded funds (ETFS) that track various bond indexes;
(3) buying mutual funds that are designed to profit from falling bond prices;
(4) buying Treasury Inflation-Protected Securities (TIPS).


See:

"SHORT-SELLING
If you have high tolerance for risk, think about selling bonds short.
This strategy involves selling borrowed bonds in a margin account in
the hope that their prices will fall. You can also short any of six
exchange traded funds (ETFS), called iShares, that track various bond
indexes. Since long-term bonds are the most volatile, the 7-to-10 year
and 20-plus year Treasury bond ETFs offer the greatest opportunity for
short-selling gains.
 The risk, of course, is that if bonds rally, you'll have to replace
your borrowed securities at a higher price. You also must reimburse
the lender for any interest paid out while you hold the short
position. You may be liable for other fees, too.
 Two no-load mutual funds also offer a chance to profit from falling
bond prices: Rydex Juno (RYJUX ) and ProFunds Rising Rates
Opportunity. But unlike short-selling, you don't need a margin
account, and you won't owe lenders any interest."
source:
BusinessWeek: Higher Rates: A Survival Kit
http://businessweek.com/magazine/content/04_19/b3882119_mz070.htm

"Betting against bonds"
http://www.usatoday.com/money/perfi/columnist/netgains/2004-06-16-betting-against-bonds_x.htm

"How to Short T Bonds"
http://www.forbes.com/columnists/forbes/2003/0811/106.html

"Inverse Bond Funds - Betting Bond Prices Go Lower"
http://www.buyupside.com/articles_other/inversebondfunds.htm

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Here are the websites of some of the specific investment ideas
mentioned in the articles above:

"Rising Rates Opportunity ProFund "
http://www.profunds.com/profiles/profile.asp?id=69

"Potomac ContraBond Fund (PCBDX)"
http://www.potomacfunds.com/contrabond_fund.jsp

"Rydex Juno Fund"
http://www.rydexfunds.com/website/fund_info_fset.cfm?rydexfundid=14

"Treasury Inflation-Protected Securities"
http://www.treasurydirect.gov/indiv/products/tips_glance.htm

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search strategy:
"from falling bond prices" 

I hope this helps.  Good luck!

Buying into bond funds is quite helpful. Shorting Treasury Bonds I
don't think is generally practible for a retail investor.

Rydex Juno, RYJCX, is a short (bear) fund that shorts long bonds
(using futures as a trading vehical.) My source,
http://www.fasttrack.net shows the correcloation between RYJCX and
long bonds is 98% percent or more. The major attraction is that using
RYJCX, you can short bonds in a retirement account.

Otherwise, you can short SHY,TLT,IEF,AGG,TIP . .  . all excahnge traded bond funds.