Lensflares aren't the ordeal they seem to be. Although you do need Photoshop to use the "render Lensflare Filter"...youcan still probably fake it with airbrushing using the same layer setup I show below.

Step 1: Choose your image

okay...so it's not really a step but i had to show you a "before" picture. :)

Step 2: Layer Setup

Create a new layer above your background layer. Fill it with 100% black and change the layers blending mode to "Screen".

"Screen" makes the black invisible so only stuff that is lighter than black will show up on this layer...why is that important?..You'll see !

Step 3: apply the filter

Make sure you are applying the lensflare to the black filled layer and not the background layer.

Boom! There's the Lensflare...only problem is that it's a little bright and in the wrong place.

No problem! Choose your move tool.
(keyboard shortcut = V)

Step 4: Move it

Now you can drag your lensflare anywhere on the pic that you want to. You can also continue to work on the picture beneath the lensflare without screwing up the effect. If the flare is too bright or the wrong color..you can recolor the flare without messing up the picture. Cool eh?