Exchange-traded funds

, or ETFs, may be one of this year's hottest investing trends, but it's leaving individual investors thirsty for more information.

ETFs are hybrid funds that trade on an exchange and are priced throughout the trading day. These funds have been enormously popular, posing a threat to traditional mutual funds. They offer investors diversification by tracking a sector or a market index, but act more like stocks in that they can be traded, sold short or purchased on margin. (For more on exchange-traded funds, see this recent

story.)

Despite this popularity, there are very few sites that focus on the ETF market as a whole, giving comparative information about the performance of different exchange-traded funds. If an investor wanted to play the technology sector, for example, there are several tech-oriented ETFs from which to choose, but little analysis about which fund to choose. For now, investors are best served by hitting the Web sites of companies that issue exchange-traded products and of the news organizations that follow ETFs closely.

A number of firms that have different types of exchange-traded products have Web sites about the funds.

State Street Global Advisors

, which launched the first ETF (called the SPDR) in 1993 and recently launched seven new ETFs called

streetTracks, has information on its

site.

Barclays Global Investors

, which

launched more than 50 of its iShares index-tracking funds this year, has a

site dedicated to the products.

The market for ETFs and

HOLDRs

, a similar exchange-traded

product offered by

Merrill Lynch

, has grown substantially this year. Total assets of ETFs and HOLDRs was around $57 billion at the end of September, almost double the $33.9 billion in assets posted last year, according to the

American Stock Exchange, which sees about 55% of its daily trading volume dedicated to these funds.

Recent studies show that many individual investors still know very little about exchange-traded products, even though they are eating up a growing percentage of new cash. A recent

Boston Research Group

survey of financial advisers and individual investors found that only 17% of investors know what exchange-traded funds are, even though 76% are aware of a specific ETF product.

That ignorance could be due to a lack of information. Even though the firms offering exchange-traded vehicles have educational Web sites and the American Stock Exchange offers information and updated quotes on its

site, there is very little research available to individuals.

Investment banks such as

Morgan Stanley Dean Witter

and

Salomon Smith Barney

put out research reports on the funds, but that information is usually reserved for their clients. However, Salomon plans to put out explanatory information about ETFs in the next few months that anyone can access via its

site.

Information, Please
For the uninitiated, here is a list of other sites that provide information on exchange- traded funds and HOLDRs.

Barclays Global
Investors iShares

Dow Jones Indexes

Merrill Lynch
Select Sector SPDRs

Merrill Lynch HOLDRs

Nasdaq QQQ

Standard & Poor's Indices

State Street Global Advisors SPDRs and streetTracks

As for what else is accessible to individual investors, many market watchers say that, so far, the American Stock Exchange seems to have the most complete Web site for ETF information. The site gives quotes and a fact sheet about each product that includes year-to-date performance, distribution history and expenses, as well as the fund's holdings and sector weightings. The exchange plans on providing more ETF information via the Web in the future, especially as more firms roll out new products.

"From the Amex's point of view, information on the availability of the funds, the portfolio of the funds we have here and getting people to understand what they are and how they work is critical," says Amex spokesman Bob Rendine.

Charles Schwab's

Web

site gives an explanation of how ETFs work, describes the products and lists the advantages of investing in exchange-traded products. Schwab's center for investment research may consider doing a study on the products if enough investors express interest, says Schwab spokesman Morrison Shafroth, who notes that most inquiries about ETFs have come from its clients who actively trade.

Morningstar's

Web

site lists quotes for exchange-traded funds and plans to add Quicktake reports giving more information about ETFs before the end of the month, says Russ Kinnel, Morningstar's director of fund analysis.

And many financial planners recommending the funds are jumping on the bandwagon to educate their clients about ETFs. Diahann Lassus, a certified financial planner based in New Providence, N.J., says she is including information about ETFs in her quarterly newsletter to clients.

"We're the ones that are bringing

ETFs up with our clients," says Lassus. "I've not run into many clients who have heard something about them, except for the ones who watch

CNBC

."

Watching "Squawk Box" isn't the only place to learn about exchange-traded funds --

TheStreet.com

also provides news on the latest developments in ETFs, along with a weekly

performance chart.

Indexfunds.com also has coverage on ETFs.