The most obvious answer is, just keep doing heroics and deal with the elitist hate.
Other than that, Strength is your primary stat. Period! So your weapon (agility) and your relic (intellect) need to be replaced with items with Strength. In addition to that, your helmet and one of your rings are itemized for tanking (Dodge, Parry, Block).
You want to focus on replacing your poorly itemized pieces asap, as well as the crafted pvp items you have equipped (Gloves, Belt, Pants). The stats you want the most are: Strength (Over everything else), Hit (To Cap), and Expertise (To Cap). At this point Mastery, Crit, and Haste are next in line. If you want to read more on this check out the post below.
As far as talents go, your 3 points in Clarity of Purpose are completely wasted and would be much better spent in Seals of the Pure (Tier 1 of the Protection Tree). You shouldn't be healing yourself at all in a dungeon (And if you absolutely have to, you should be using a 3 point Word of Glory).
I would personally replace Glyph of Judgement with Glyph of Templar's Verdict as it will yield a much higher dps increase than Glyph of Judgement.
I would recommend that you try and find a guild with friendly members that will run dungeons with you while you learn your rotation and collect better gear.
If you are not an addon purest and would like a rotation helper, CLCRet is a great tool to help you learn your rotation. It keeps track of all of your cooldowns and buffs and tells you via an icon what ability should be used next to continue your optimal rotation. It isn't perfect, but it will help you learn timings (like making sure Inquisition doesn't fall off).
If you want to read some really good information about Retribution Paladins (Specs, Rotations, Glyphs, Stats, Reforging, Gemming, Enchanting, Cooldowns, etc) I recommend this post on Elitist Jerks.