So, here's Mamacita off of the guys' new album III. My version doesn't have all 
the bells and whistles they use, but it's a pretty hot tune if you've got just an acoustic guitar.

Intro: C  E  Am  F

Verse 1:

           C                     E                   Am                         F   
If you read my lips,   If you got junk in the trunk
                   C                   E   Am             F
Come and get, get low,    everybody it's time to party

Prechorus: 

Dm                    Am
You got a JLO  (aye, aye, aye)
Dm                                  Am
You can make a cholo (cry, aye, aye)
Dm                                                  Am
Oh, you know you make me go (aye, aye, aye)
F
Oh, aye, aye, aye
G
Oh, aye, aye aye!

Chorus:

C                      E                         Am                                     F
Ay Mamacita, my little chica, you got me loco singin' 'aye, aye, aye'
C                E                                            Am                  F
Ay Senorita, nothin' could be sweeter, we cross the border, you and I, aye, aye 
C                             E                    
Aye, aye aye, ohh aye, aye, aye, ohh
Am                                      F
You got me loco singin' 'aye, aye, aye'

Verse 2:
C                         E       Am                F
Hot salsa chick,   excuse me Ms. (aye, aye, aye)
C                                      E 
Gimme', gimme' amor, por favor
Am               F
Everybody, it's time to party

(Prechorus)

(Chorus)

Bridge:
The bridge in this song is kinda weird, so I would just suggest playing an Am as a filler

Interlude:
C               E                Am
Whooaaa, Whooaaa, Whooaaa,
Am                                     F
You got me loco singin' 'aye, aye, aye'

From here you play the chorus a few more times, then end it all with a C.

Hope you enjoyed! Have fun playing this stinkin' awesome song!