The world's top value investors love it when their best stock ideas are selling at bargain-basement prices. For those rarefied investors, companies offering fire-sale prices become no-brainer buys. So regular investors like you and me would do well to emulate the masters and look at companies offering a "buy-one-get-one" sale on their stocks.

Less than a year ago these companies were trading for at least twice the value they currently do. While you'll naturally want to do more due diligence before buying, this might be an opportunity to pick up some quality companies at a severe discount. The market is down only 2% from its 52-week highs, so make sure there's nothing seriously wrong with these stocks before you plug them into your portfolio.

Hanging up on growth
Both north and south, the wireless world would seem to be an easy win for companies plying their trade there, since the mobile market remains one of the jewels of an otherwise anemic economy. The market researchers at Gartner say that equipment spending will be $377 billion this year, a 10.8% increase from 2011, while telecom services spending is set to hit about $1.69 trillion, a 1.4% increase.

Yet investors continue to hang up on NII Holdings (Nasdaq: NIHD), the South of the Border Nextel. NII markets its services under the Sprint Nextel brand, generating 50% of its revenues from Brazil and another third from Mexico. But it's struggling to advance regardless of where it operates, as fiscal first-quarter revenues came in essentially flat from the year-ago period and profits plummeted 89% from the year-ago period.

It's been upgrading its network, which it blamed for the lower earnings, but its 3G network is only just getting up and running, while rivals America Movil and Telefonica (NYSE: TEF) already have well-established services. The former is the dominant force in Mexico while the latter rules Brazil.

So far, NII has been able to make up in average revenue per user what it lacks in distribution. It has an ARPU of $42 in Mexico, whereas America Movil generates just $14. But that's down $7 per user from last year as customers chose lower-cost plans, and it faces rising customer churn rates: 2.07% in the first quarter compared to 1.61% a year ago.

Investors still see a chance of it turning its operations around, as almost 92% of the 414 Motley Fool CAPS members rating NII Holdings believe it will outperform the broad market indexes. Let me know in the comments section below if you'll also be disconnecting from the wireless provider if things don't improve.

A difficult sequence of events
Wireless chip maker RF Micro Devices (Nasdaq: RFMD) was another company that couldn't seem to grab more of the money being spent on mobile, as revenues dropped 5% from last year's efforts and profits were down more than 4%. Although it did post higher revenues sequentially, it reported that current-quarter revenues would at best be flat from the first quarter, but also could be down as much as 5%. It estimates that growth won't return until the December quarter.

While NII is seeking to exploit the 3G market, the Fool's Anders Bylund previously remarked that emerging 4G opportunities are RF Micro's best chance for regaining momentum and market share. That doesn't mean it will be easy, as rivals like Skyworks Solutions (Nasdaq: SWKS) have gained significant leads by making the riding of Apple's coattails into an art form. As a result, Anders dubs RF Micro a speculative, long-term play.

Of course, Skyworks might want to be wary of being too dependent on Apple, as RF Micro once rode a similar wave higher on the back of Nokia (NYSE: NOK). While it seems hard to imagine Apple unraveling the way Nokia has, the Finnish handset maker was once on top of the world, as the iPhone maker is today, and it has turned into a shell of its former self.

More than 700 members have weighed in on RF Micro Devices over on CAPS, and 94% think it will be able to bounce back. Dial up any concerns you have on the chip maker in the comments box below, especially on whether you think the slowdown in spending by its customers will take it longer to recover than it expects.

Have half a mind
The mobile revolution still has a lot of room to run despite the poor performance of NII and RF Micro. Indeed, The Motley Fool thinks we're still in early innings on what may be a trillion-dollar revolution. Find out which stock the Fool will be cashing in on in a special report you can download for free! But hurry, because it's available only for a limited time.