Changing caption style

Talk to the div for the image+caption like this (in your theme’s “style.css”):

.wp-caption{
	...
}

And the p for the caption line is here:

.wp-caption p.wp-caption-text {
	...
}

Also make sure to have the following in your stylesheet for the alignment to work correctly:

.alignleft {
    float: left;
}

.alignright {
    float: right;
}

Oh, and here is a more detailed thread on the topic 😉
http://wordpress.org/support/topic/189152?replies=4

You can apply float: left while inside of a block and they will line up in little rows. works best with images of the same width (for one row) or height and width for multiple rows.