To the original question, it is rare to see all the necessary parameters for a device in the data sheet, particularly transistors. Some diode manufacturers do put all the necessary parameters in the datasheet.
The model file is here for the MOSFET (and it includes all the necessary parameters).
Just in case the link goes stale, here is the model:
There is a list of MOSFET parameters here as used in SPICE.
.SUBCKT irfz44n 1 2 3
**************************************
* Model Generated by MODPEX *
*Copyright(c) Symmetry Design Systems*
* All Rights Reserved *
* UNPUBLISHED LICENSED SOFTWARE *
* Contains Proprietary Information *
* Which is The Property of *
* SYMMETRY OR ITS LICENSORS *
*Commercial Use or Resale Restricted *
* by Symmetry License Agreement *
**************************************
* Model generated on Apr 24, 96
* Model format: SPICE3
* Symmetry POWER MOS Model (Version 1.0)
* External Node Designations
* Node 1 -> Drain
* Node 2 -> Gate
* Node 3 -> Source
M1 9 7 8 8 MM L=100u W=100u
* Default values used in MM:
* The voltage-dependent capacitances are
* not included. Other default values are:
* RS=0 RD=0 LD=0 CBD=0 CBS=0 CGBO=0
.MODEL MM NMOS LEVEL=1 IS=1e-32
+VTO=3.56214 LAMBDA=0 KP=39.3974
+CGSO=1.25255e-05 CGDO=2.2826e-07
RS 8 3 0.0133305
D1 3 1 MD
.MODEL MD D IS=9.64635e-13 RS=0.00967689 N=1.01377 BV=55
+IBV=0.00025 EG=1.08658 XTI=2.9994 TT=1e-07
+CJO=1.39353e-09 VJ=0.5 M=0.42532 FC=0.5
RDS 3 1 2.2e+06
RD 9 1 0.0001
RG 2 7 2.20235
D2 4 5 MD1
* Default values used in MD1:
* RS=0 EG=1.11 XTI=3.0 TT=0
* BV=infinite IBV=1mA
.MODEL MD1 D IS=1e-32 N=50
+CJO=1.52875e-09 VJ=0.5 M=0.584414 FC=1e-08
D3 0 5 MD2
* Default values used in MD2:
* EG=1.11 XTI=3.0 TT=0 CJO=0
* BV=infinite IBV=1mA
.MODEL MD2 D IS=1e-10 N=0.408752 RS=3e-06
RL 5 10 1
FI2 7 9 VFI2 -1
VFI2 4 0 0
EV16 10 0 9 7 1
CAP 11 10 2.06741e-09
FI1 7 9 VFI1 -1
VFI1 11 6 0
RCAP 6 10 1
D4 0 6 MD3
* Default values used in MD3:
* EG=1.11 XTI=3.0 TT=0 CJO=0
* RS=0 BV=infinite IBV=1mA
.MODEL MD3 D IS=1e-10 N=0.408752
.ENDS
The schottky model is here, and again, in case the link goes stale:
*SRC=MBR1560CT;DI_MBR1560CT;Diodes;Si; 60.0V 15.0A 5.00ns Diodes Inc. Schottky - One element of device
.MODEL DI_MBR1560CT D ( IS=11.3u RS=2.64m BV=60.0 IBV=25.0u
+ CJO=530p M=0.333 N=1.87 TT=7.20n )
Short answer - In 20 years I haven't done so once.
Longer answer:
It depends a lot on the field you're working in.
Do you have to worry about rise times, fall times etc... Yes. Not for every signal, in fact you normally only care about them for a tiny fraction of signals. Knowing which ones matter is an important part of the job.
But for the ones that do matter the formulas in the book are fairly useless, they are great for a first pass approximation but if a rough approximation is good enough it's probably not a signal that's too critical to start with. Any real world circuit is far too complex to analyse in detail by hand, instead you run a simulation rather than using the formula in the book and the simulator already knows the formulas.
So the book formulas are good because then you understand what the simulator is doing behind the scenes and the assumptions and limitations in what it is doing. There is a lot to be said for having an appreciation of what your tools are doing in the background, if nothing else it helps figure out why they break or complain about things when they do. But you don't need to remember or even be able to work through the maths that is going on behind the curtain.
And then ultimately no matter what the simulator tells you after you've build it you check in the real world because as the saying goes in theory theory and practice are the same. In practice they aren't.
Best Answer
Be aware that small-signal parameters assume linear operation, which usually means that the intended operating parameters vary over a small range. It is apparent that the intended application of this device is as a switch, operating over a very large range. Deriving small-signal parameters from this data sheet will likely result in gross approximations that vary with temperature, and vary from device-to-device.
Data sheet actually supplies \$g_m\$ of 370 Siemens, but that data point is far beyond any useful bias point (the device would very quickly go up in smoke).
Data sheet also supplies ID/VDS curves from which small-signal parameters might be derived. Again, these plots are scaled to concentrate on large currents, scrunching the more useful region of lower ID current, where you most likely will be biased. Operating at high currents (many amps) and single-digit volts of \$V_{ds}\$ will overheat this device:
Let's check that rogue forward transconductance of 370 S with a more reasonable bias point of 1V, 1A where the device only dissipates 1W:
I eyeball-estimate \$V_{gs}\$ of 2.4V at this bias point.
Use another point from this curve to calculate \$g_m\$: \$V_{gs}=2.5V, I_D=2A\$ @ Vds=1V
The difference in \$V_{gs}\$ of 0.1V yields a 1A change in \$I_D\$. Thus the transconductance \$g_m = 10 S\$. This is far different from 370 at that distant bias point of 10V & 220A.
The parameter \$r_o\$ would be derived from the slope of the bottom-most curve (Vgs=2.5V). Since it is not linear, you'd only get a very rough estimate of its value.
Be aware that most of the provided data covers a bias region where the device would dissipate-to-death from overheat. Do a dissipation calculation to ensure that at all bias points, this device won't overheat.