How do i import pictures from my Mac to my iPod touch?

I got this from the iTunes Help, and put some necessary emphasis:

To add photos to your iPod:

Connect your iPod to your computer using the cable that came with your iPod.

When the iPod icon appears in iTunes, select it (it, being your iTouch icon appearing after the sync is finished) and click the Photos tab.

Select “Sync photos from” and choose the photo application or folder that contains the photos you want from the pop-up menu.

If you're using Adobe Photoshop Album 2.0 or later, or Adobe Photoshop Elements 3.0 or later, you can export photos directly from those applications to your iPod by choosing Photoshop Album or Photoshop Elements from the pop-up menu.

Choose whether to move all your folders or albums, or only selected folders or albums.

To also move the full-resolution versions of these photos to your iPod, select “Include full-resolution photos.”

Note:You should select this option if you plan to move the photos from your iPod to another computer. This option isn't available on iPhone.