Small-cap stocks, as a group, struggled to find their footing Tuesday amid mixed news from a variety of sectors.

Waste Industries USA ( WWIN) ranked among the biggest price gainers overall, soaring 28.9% after an investor group led by founder-and-Chairman Lonnie Poole and CEO Jim Perry offered to take it private for $36.75 a share in cash. The group already owns about 51% of the company. Shares of the Raleigh, N.C., waste-services company vaulted $7.36 to $35.83.

Columbus McKinnon ( CMCO), an Amherst, N.Y., construction-equipment maker, leapt 17.8% to $30.30 after pro-forma income hiked up 22.7% to 54 cents a share, or $10.4 million, in the fiscal second quarter. That easily tops Wall Street's consensus for 47 cents a share, per Thomson Financial.

Arizona's JDA Software ( JDAS), meanwhile, doubled its non-GAAP third-quarter earnings to 40 cents a share from last year and careened past Wall Street's 29-cent views. The management-software firm also brought in higher-than-expected revenue of $93.7 million. Shares ratcheted up $2.52, or 11.8%, to $23.80.

JDA Software's gains lent support to the S&P SmallCap 600, and all of the above names helped give legs to the Russell 2000. Both trackers recently added around 0.5% after straddling the flat line for much of the day.

In initial public offerings, China-based jewelry designer Fuqi International ( FUQI) surged 25.4% after pricing some 7 million shares at $9 each, along with an underwriters' option for another 1.1 million shares to cover any overallotments. Shares were trading at $11.29.

CVR Energy ( CVI) offered 20 million shares at $19 a pop, along with a 3-million-share underwriters' option. Shares of the Texas-based fuel refiner were climbing 8.6% to $20.64.

General Steel ( GSI), a China-based steel manufacturer, rode high after pegging third-quarter income at $7 million to $7.5 million on revenue of $300 million to $340 million. The analyst who follows the company is seeking a $7 million profit on revenue of $286.5 million. Shares were up $1.43, or 12.2%, to $13.17.

And Copernic ( CNIC) had a quick rise on news that it has added an Apple ( AAPL) iPhone/iPod Touch-optimized user interface to its Copernic Mobile software, which allows users to search and access PC-based content from their mobile devices.

The Canada-based company said it's "actively working to license the product to wireless operators." Shares spiked 20.1% to $3.40.

On the same token, education-travel company Ambassadors ( EPAX) plummeted 43% after saying that net enrolled participants for its 2008 travel programs are down 29.8% from comparable numbers this time last year. The Spokane, Wash., outfit believes this will impact earnings along with "inflationary pressures on future program costs" such as the weakening dollar and airline-fuel surcharges, among other things.

Ambassadors additionally came in above third-quarter top- and bottom-line estimates, but shares still dwindled $17.17 to $22.78.

Ultra Clean ( UCTT), a Menlo Park, Calif., semiconductor firm, lost 12.1% to $13.55 after its third-quarter profit dropped 36% from last year to 16 cents a share, or $3.5 million -- 9 cents shy of analysts' targets. Revenue, at $95.5 million, was also lower than expected.

Also slumping on below-par financials was IHOP ( IHP). The Glendale, Calif., pancake purveyor said third-quarter income totaled 60 cents a share, excluding items, on $91.4 million in revenue. Analysts were looking for 68 cents a share on revenue of $93.2 million. Shares were off 3.9% to $61.04.