Google is probably your best friend.
Anyway just feed you infos.
LGA1155 H71, B75, H77, Z77 goes along with Ivy Bridge/Sandy Bridge iX-3XXX/k or iX-2XXX/k
LGA1150 H81, B85, H85, H97, Z87, Z97 goes along with Haswell iX-4XXX/k
LGA1151 Z170 goes along with Skylake iX-6XXX/k
For PSU wattage....
300w-350w
For any processor with no Graphics Card or a single Graphics Card GTX750, R7 260X, GTX750ti or below. No overclocking is recommended.
450w
For any processor with any single Graphics Card with R9 270 or GTX760, GTX950, GTX960 or below. No overclocking is recommended.
500w-550w
For any processor with any single Graphics card with R9 380 or GTX970 and below. Overclocking can be done for any of CPU & GPU.
600w-650w
For any processor with any single Graphics card. Except for special exclusive custom made Graphics Card by selected brands. Overclocking can be done for any of CPU & GPU.
750w
For any processor with single custom made Graphics Card by selected brands, OR dual Graphics Card that is GTX970 and GTX 980. Mild overclocking can done for any of CPU & GPU.
850w
For any processor with dual Graphics Card such as R9 290, R9 290X and 980ti, Titan X. No overclocking is done for any of CPU & GPU.
1000w
For any processor with dual Graphics Card not including exclusive custom made Graphics Card. With CPU & GPU being overclocked.
1200w and above.
For any processor with ANY dual Graphics Card. With CPU & GPU being overclocked.
Also depends on the PSU you are buying, choose good reputable brands such as, Superflower, EVGA, Seasonic, Corsair (AX, HX series), FSP Aurum.
As for cases....
It goes hand in hand with the motherboard you selected. Also the size of the Graphics Card may depends on your chassis you buy.
Both motherboard and chassis relates to this few...
mITX
mATX
ATX
EATX (Very rare boards will land here)
An ATX size Chassis can fit anything from ATX or below.