Here's a song for the beginners, the original version of this song (performed by the Monkeys) is even simpler as far as the guitar goes. Smashmouth to me are not renowned for there great guitar riff in their songs, but what they do use they incorporate well. For all you up and coming song writers, you should have a listen to the original of this song and compare it to this version and see how Smashmouth have adapted it.
For the beginners: you'll most probably have trouble with hammering (represented by the HO on the tab) in the intro riff. To play it correctly you have to lay your 1st finger across the 5th and 4th strings and hammer with your 3rd finger on the 5th string. Make the notes flow evenly one after the other like this, 123123123123123 (listen to the midi). Most students when playing this song, play quicker on the hammer notes, so it comes out sounding like 12 3 12 3 12 3 (say this with a slight pause where the spaces are).