I'm no expert, but I will help as I can.

1)If you look over in the upper right hand corner of the screen, you will see yellow, green, blue, etc gems with numbers next to them. Those would represent the number of shards you control. I also believe that you can see this in your city management screen.

2)If you are playing as Paradien (the "good" magical race), there is a spell whose name escapes me right now that will allow you to create an outpost without needing to create a pioneer.

3)Research the magic tech tree, especially if you have a Conclave. I believe some of the spell you can use depend on your race/faction. You can also get more spells depending on which champions you can recruit.

4)Armor should be in the warfare tree. I can't recall if there are buildings in the civ tree that also help.

I am sure that people who are more knowledgeable than me will chime in shortly. In addition, there should be an Elemental Wiki page up and running soon.

Hope this helps.

More buildings are unlocked through your tech tree. But at a certain point, you'll have unlocked all the buildings. So if you can't build anything new in a city and can't unlock buildings in your tech tree anymore, you're done building in that city. Just switch to producing gildar/research/mana/growth once you've built all that you wanted in a city.

Equipment for heroes can be obtained in 3 ways

- Loot it 

- Trade it in from new heroes/enemy sovereigns that surrendered (enemy sovs usually carry a lot of spare equipment)

- Buy it. When you are in freindly territory, a 'SHOP' button will appear. Click it and you'll get the possibility to buy all the items that faction has researched up until then. This is a very pricey method though.

In addition to the great answers above:

#3 There are 6 ways to obtain new spells. These are, from most to least common:

- The 6 Spellbooks; Air, Earth, Fire, Water, Life, Death. You can pick spellbooks at the start of the game and most heroes start with one or two. Also, the Decalon trait allows you to research and buy all Spellbooks. All, except Death/Life, because they are mutually exclusive. All spellbooks have 5 levels of spells.

- The Mage path traits. These include Summoning spells and various other groups of spells you can pick at level-up.

- Research the 'Magic' tree. Some of the most powerful Strategic spells can be found here. Some spells are Kingdom/Empire only.

- Some faction traits grant your faction some unique spells. Magnar and Resoln each have such a spell trait. Also, some races grant a racial ability that's very similar to a spell.

- Quests: a few quests grant you a spell. I only ever had the useless 'alchemy' spell, but rumors are, there's actually a useful spell to be had.

- Unique heroes with unique spells. Keep your fingers crossed and hope for a cool hero each time you reach a Fame threshold. At 200 and 400, there's a solid chance you'll get a hero with an unique ability. Some of the best heroes are quest rewards, so quest as much as you can!