NEW YORK (AP) — With a big selection of legal tunes and music videos available to download for free, SpiralFrog sounds like a music junkie's dream.

Too bad the online service is so frustrating to use.

The site, conceived as way to get fans of music-swapping networks on the straight-and-narrow, was opened to US and Canadian users in mid-September. Unlike Apple Inc.'s iTunes, Napster and other online music stores, it's fully supported by advertising.

Anyone can peruse the site, but those who want to download songs or videos must register and then install SpiralFrog's download manager. And you can transfer the content from your PC to digital players — though it won't work on iPods or Microsoft Zunes.

Annoyances emerged as soon as I started using SpiralFrog.

For one, I couldn't download more than one song or video at a time. Users can fill a queue with tracks, but must go back to somewhere on SpiralFrog's site and click a button after each song is transferred to start the next.

This meant that to download an entire album I had to stay near my computer. And while I'm often stuck there anyway, it's a pain to interrupt whatever I'm doing to click through to the next song.

I tried beating the system by setting up two queues on two different Web browsers, but SpiralFrog was wise to my game: The site interrupted both downloads.

Interestingly, the aspect of the site I figured would be the most obnoxious — the advertising — was actually fairly unobtrusive. I only noticed the ubiquitous banner and sidebar ads on the site when I was looking for them.

The selection — at nearly 1 million tracks from labels large and small, including Universal Music Group and EMI Music Publishing — is decent. SpiralFrog founder Joe Mohen said it will grow to more than 2 million songs by early 2008.

The quality is pretty good — the songs are encoded at between 128 and 192 kilobits per second, the lower end of which is comparable with standard tracks downloaded from Apple's iTunes Store. I also liked that the tracks include album art.

Videos can be downloaded in high- or low-resolution formats. The low-resolution videos are encoded at 300 Kbps, while higher-quality versions are encoded at 1,000 Kbps. Users also can watch videos on the SpiralFrog site.